- The removed functions are not used in Iavl, Cosmos-sdk and tendermint repos
- Code-hygenie `whoop whoop`

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

Also, document time_iota_ms.

Closes #3723

Commits:

* config: Add ConsensusParams when generating testnet config (#3723)

* docs: Add explanation of time_iota_ms (#3723)

* Update changelog_pending (#3723)

* Remove file heap.go

- cmn.Heap is not being used in cosmos-sdk, iavl nor tendermint repo.

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* changelog entry

* Update CHANGELOG_PENDING.md

closes #2432

* change invocation of NewNode across

* custom reactor name are prefixed with CUSTOM_

* upgate changelog pending

* improve comments

* node: refactor NewNode to use functional options

Calling ensurePeers outside of ensurePeersRoutine can lead to nodes
disconnecting from us due to "sent next PEX request too soon" error.

Solution is to just dial addrs we got from src instead of calling
ensurePeers.

Refs #2093

Fixes #3338

As per #2127, this refactors the RequestCheckTx ProtoBuf struct to allow for a flag indicating whether a query is a recheck or not (and allows for possible future, more nuanced states).

In order to pass this extended information through to the ABCI app, the proxy.AppConnMempool (and, for consistency, the proxy.AppConnConsensus) interface seems to need to be refactored along with abcicli.Client.

And, as per this comment, I've made the following modification to the protobuf definition for the RequestCheckTx structure:

enum CheckTxType {
  New = 0;
  Recheck = 1;
}

message RequestCheckTx {
  bytes tx = 1;
  CheckTxType type = 2;
}

* Refactor ABCI CheckTx to notify of recheck

As per #2127, this refactors the `RequestCheckTx` ProtoBuf struct to allow for:

1. a flag indicating whether a query is a recheck or not (and allows for
   possible future, more nuanced states)
2. an `additional_data` bytes array to provide information for those more
   nuanced states.

In order to pass this extended information through to the ABCI app, the
`proxy.AppConnMempool` (and, for consistency, the
`proxy.AppConnConsensus`) interface seems to need to be refactored.

Commits:

* Fix linting issue

* Add CHANGELOG_PENDING entry

* Remove extraneous explicit initialization

* Update ABCI spec doc to include new CheckTx params

* Rename method param for consistency

* Rename CheckTxType enum values and remove additional_data param

- libs/errors: commented out errors.go
- libs/common: unused colors.go
- libs/db: unused debugDB

Signed-off-by: Marko Baricevic <marbar3778@yahoo.com>

* changelog and version

* Add section on ABCI changes

* Update ABCI upgrade section to include events examples

* update upgrading

* more upgrading and changelog

* update changelog from pending

* refer to #rpc_changes

* minor word changes

* Make RPC bind to localhost by default

* Add CHANGELOG_PENDING entry

* Allow testnet command to override RPC listen address

* Update localnet test to bind RPC to 0.0.0.0

* Update p2p test to bind RPC to 0.0.0.0

* Remove rpc-laddr parameter

* Update localnet to use config template with RPC listen address override

* Use config template override method for RPC listen address

* Build config template into localnode image

* Build localnode image locally before starting localnet

* Move testnet config overrides into templates

* Revert deletion of config overrides

* Remove extraneous config parameter overrides

Refs #3656

* node: run whole func in goroutine, not just logger.Error fn

Fixes #3741

* add a changelog entry

* abci/example: use base64 for update validator set

* update kvstore/README.md

* update CHANGELOG_PENDING.md and abci/example/kvstore/README.md

* Refactor signature of Application.CheckTx

* Refactor signature of Application.DeliverTx

* Refactor example variable names for clarity and consistency

* Rename method variables for consistency

* Rename method variables for consistency

* add a changelog entry

* update docs

* node: fix a bug where `nil` is recorded as node's address

Solution

  AddOurAddress when we know it
  sw.NetAddress is nil in createAddrBookAndSetOnSwitch
  it's set by n.transport.Listen function, which is called during start

Fixes #3716

* use addr instead of n.sw.NetAddress

* add both ExternalAddress and ListenAddress as our addresses

Follow up to #3643

* update changelog

* do not ignore errors returned by PublishWithEvents

## PR

This PR introduces a fundamental breaking change to the structure of ABCI response and tx tags and the way they're processed. Namely, the SDK can support more complex and aggregated events for distribution and slashing. In addition, block responses can include duplicate keys in events.

    Implement new Event type. An event has a type and a list of KV pairs (ie. list-of-lists). Typical events may look like:

"rewards": [{"amount": "5000uatom", "validator": "...", "recipient": "..."}]
"sender": [{"address": "...", "balance": "100uatom"}]

The events are indexed by {even.type}.{even.attribute[i].key}/.... In this case a client would subscribe or query for rewards.recipient='...'

    ABCI response types and related types now include Events []Event instead of Tags []cmn.KVPair.
    PubSub logic now publishes/matches against map[string][]string instead of map[string]string to support duplicate keys in response events (from #1385). A match is successful if the value is found in the slice of strings.

closes: #1859
closes: #2905

## Commits:

* Implement Event ABCI type and updates responses to use events

* Update messages_test.go

* Update kvstore.go

* Update event_bus.go

* Update subscription.go

* Update pubsub.go

* Update kvstore.go

* Update query logic to handle slice of strings in events

* Update Empty#Matches and unit tests

* Update pubsub logic

* Update EventBus#Publish

* Update kv tx indexer

* Update godocs

* Update ResultEvent to use slice of strings; update RPC

* Update more tests

* Update abci.md

* Check for key in validateAndStringifyEvents

* Fix KV indexer to skip empty keys

* Fix linting errors

* Update CHANGELOG_PENDING.md

* Update docs/spec/abci/abci.md

Co-Authored-By: Federico Kunze <31522760+fedekunze@users.noreply.github.com>

* Update abci/types/types.proto

Co-Authored-By: Ethan Buchman <ethan@coinculture.info>

* Update docs/spec/abci/abci.md

Co-Authored-By: Ethan Buchman <ethan@coinculture.info>

* Update libs/pubsub/query/query.go

Co-Authored-By: Ethan Buchman <ethan@coinculture.info>

* Update match function to match if ANY value matches

* Implement TestSubscribeDuplicateKeys

* Update TestMatches to include multi-key test cases

* Update events.go

* Update Query interface godoc

* Update match godoc

* Add godoc for matchValue

* DRY-up tx indexing

* Return error from PublishWithEvents in EventBus#Publish

* Update PublishEventNewBlockHeader to return an error

* Fix build

* Update events doc in ABCI

* Update ABCI events godoc

* Implement TestEventBusPublishEventTxDuplicateKeys

* Update TestSubscribeDuplicateKeys to be table-driven

* Remove mod file

* Remove markdown from events godoc

* Implement TestTxSearchDeprecatedIndexing test

* Update to using go mod from dep

* Remove references to make get_vendor_deps

* Specify go version

* Set GO111MODULE=on and add -mod=readonly

* Fix exported env

* switch to using go1.12 everywhere

* Fix test scripts

* Typo:

* Prepend GO111MODULE=on

* remove dep cache

* Revert "remove dep cache"

This reverts commit 45117bda

Signed-off-by: Ismail Khoffi <Ismail.Khoffi@gmail.com>

* bring back the dependency cache and change it to cache modules instead
of vendored deps; also:

 - bump version for dependency cache
 - bump version on pkg-cache (includes modules directory)

Signed-off-by: Ismail Khoffi <Ismail.Khoffi@gmail.com>

* remove some more traces of dep:
 - remove Gopkg.(toml | lock)
 - update contributing guidlines
 - set global default in circleci (GO111MODULE=on)

Signed-off-by: Ismail Khoffi <Ismail.Khoffi@gmail.com>

* global var failed for `test_cover` with
`go: unknown environment setting GO111MODULE=true`
although the var was `GO111MODULE: on`

Signed-off-by: Ismail Khoffi <Ismail.Khoffi@gmail.com>

* Changelog pending entry

Signed-off-by: Ismail Khoffi <Ismail.Khoffi@gmail.com>

* Add bbolt dependency to go.mod

Signed-off-by: Ismail Khoffi <Ismail.Khoffi@gmail.com>

* move -mod=readonly to build flags

BoltDB's accessors will return slices that are only valid for the
lifetime of the transaction.  This adds copies where required to prevent
hard to debug crashes (among other things).

`Delete` should queue a delete operation that targets the entire
database, and not just keys that happen to be in the current batch.

Fixes #3521

The function NewNetAddressStringWithOptionalID is from a time when peer
IDs were optional. They're not anymore. So this should be renamed to
NewNetAddressString and should ensure the ID is provided.

* update changelog
* use NewNetAddress in transport tests
* use NewNetAddress in TestTransportMultiplexAcceptMultiple

So we can have an error code when rpc fails.

* Update CHANGELOG_PENDING.md
Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>

* wrap correct error
* format code

* Add `chID` label to sent/receive byte mtrics
* add changelog pending entry

Fixes #3616

Otherwise, we'll be trying to include them in each consecutive block.

The downside is that evil proposers will be able to drop valid
transactions (see #3322).

Reverts https://github.com/tendermint/tendermint/pull/3625

Fixes #3699

* update changelog

* Update changelog

- less detail about internal stuff like the `mempool`
- focus BUG FIX entries more on what was fixed rather than how

* minor cleanup.

- remove entry for GenesisDocProvider, it's being undone

* minor fix

* Allow testnet hostnames to be overridden

This allows one to specify the `--hostname` flag multiple times, each
time providing an additional custom hostname for a respective peer
(validator or non-validator). This overrides any of the
`--hostname-prefix` or `--starting-ip-address` flags.

The string array approach is taken instead of the string slice approach
(see the pflag docs:
https://godoc.org/github.com/spf13/pflag#StringArray) because the string
slice approach (a comma-separated string) doesn't allow for cleaner
multi-line BASH scripts - where this feature is intended to be used.

* Reorder conditional for clarity with simpler earlier return

* Allow for specifying peer hostname suffix

* Quote values in help strings for greater clarity

* Fix command switch

* Add CHANGELOG_PENDING entry for PR

* Allow for unique monikers

The current approach to generating monikers for testnet nodes assigns
the local hostname of the machine on which the testnet config was
generated to all nodes. This results in the same moniker for each and
every node.

This commit makes use of the supplied `--hostname-prefix` and
`--hostname-suffix`, or `--hostname` parameters to generate unique
monikers for each node. Alternatively, another parameter
(`--random-monikers`) allows one to forcibly override all of the other
options with random hexadecimal strings.

* Update CHANGELOG_PENDING entry for new command line switch

* fix peer state init to late

Peer does not have a state yet. We set it in AddPeer.
We need an new interface before mconnection is started

* pex message to soon

fix reconnection pex send too fast,
error is caused lastReceivedRequests is still
not deleted when a peer reconnected

* add test case for initpeer

* add prove case

* remove potentially infinite loop

* Update consensus/reactor.go

Co-Authored-By: guagualvcha <baifudong@lancai.cn>

* Update consensus/reactor_test.go

Co-Authored-By: guagualvcha <baifudong@lancai.cn>

* document Reactor interface better

* refactor TestReactorReceiveDoesNotPanicIfAddPeerHasntBeenCalledYet

* fix merge conflicts

* blockchain: remove peer's ID from the pool in InitPeer

Refs #3338

* pex: resetPeersRequestsInfo both upon InitPeer and RemovePeer

* ensure RemovePeer is always called before InitPeer

by removing the peer from the switch last (after we've stopped it and
removed from all reactors)

* add some comments for ConsensusReactor#InitPeer

* fix pex reactor

* format code

* fix spelling

* update changelog

* remove unused methods

* do not clear lastReceivedRequests upon error

only in RemovePeer

* call InitPeer before we start the peer!

* add a comment to InitPeer

* write a test

* use waitUntilSwitchHasAtLeastNPeers func

* bring back timeouts

* Test to ensure Receive panics if InitPeer has not been called

* p2p: initial implementation of peer behaviour

* [p2p] re-use newMockPeer

* p2p: add inline docs for peer_behaviour interface

* [p2p] Align PeerBehaviour interface (#3558)

* [p2p] make switchedPeerHebaviour private

* [p2p] make storePeerHebaviour private

* [p2p] Add CHANGELOG_PENDING entry for PeerBehaviour

* [p2p] Adjustment naming for PeerBehaviour

* [p2p] Add coarse lock around storedPeerBehaviour

* [p2p]: Fix non-pointer methods in storedPeerBehaviour

    + Structs with embeded locks must specify all methods with pointer
     receivers to avoid creating a copy of the embeded lock.

* [p2p] Thorough refactoring based on comments in #3552

    + Decouple PeerBehaviour interface from Peer by parametrizing
    methods with `p2p.ID` instead of `p2p.Peer`
    + Setter methods wrapped in a write lock
    + Getter methods wrapped in a read lock
    + Getter methods on storedPeerBehaviour now take a `p2p.ID`
    + Getter methods return a copy of underlying stored behaviours
    + Add doc strings to public types and methods

* [p2p] make structs public

* [p2p] Test empty StoredPeerBehaviour

* [p2p] typo fix

* [p2p] add TestStoredPeerBehaviourConcurrency

    + Add a test which uses StoredPeerBehaviour in multiple goroutines
      to ensure thread-safety.

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour_test.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* Update p2p/peer_behaviour.go

Co-Authored-By: brapse <brapse@gmail.com>

* [p2p] field ordering convention

* p2p: peer behaviour refactor

    + Change naming of reporting behaviour to `Report`
    + Remove the responsibility of distinguishing between the categories
    of good and bad behaviour and instead focus on reporting behaviour.

* p2p: rename PeerReporter -> PeerBehaviourReporter

* libs/db: conditional compilation

For cleveldb: go build -tags cleveldb
For boltdb: go build -tags boltdb

Fixes #3611

* document db_backend param better

* remove deprecated LevelDBBackend

* update changelog

* add missing lines

* add new line

* fix TestRemoteDB

* add a line about boltdb tag

* Revert "remove deprecated LevelDBBackend"

This reverts commit 1aa85453f7.

* make PR non breaking

* change DEPRECATED label format

https://stackoverflow.com/a/36360323/820520

* mempool: remove only valid (Code==0) txs on Update

so evil proposers can't drop valid txs in Commit stage.

Also remove invalid (Code!=0) txs from the cache so they can be
resubmitted.

Fixes #3322

@rickyyangz:

In the end of commit stage, we will update mempool to remove all the txs
in current block.

// Update mempool.
err = blockExec.mempool.Update(
	block.Height,
	block.Txs,
	TxPreCheck(state),
	TxPostCheck(state),
)

Assum an account has 3 transactions in the mempool, the sequences are
100, 101 and 102 separately, So an evil proposal can only package the
101 and 102 transactions into its proposal block, and leave 100 still in
mempool, then the two txs will be removed from all validators' mempool
when commit. So the account lost the two valid txs.

@ebuchman:

In the longer term we may want to do something like #2639 so we can
validate txs before we commit the block. But even in this case we'd only
want to run the equivalent of CheckTx, which means the DeliverTx could
still fail even if the CheckTx passes depending on how the app handles
the ABCI Code semantics. So more work will be required around the ABCI
code. See also #2185

* add changelog entry and tests

* improve changelog message

* reformat code

## Description

Refs #2659

Breaking changes in the mempool package:

[mempool] #2659 Mempool now an interface
    old Mempool renamed to CListMempool
    NewMempool renamed to NewCListMempool
    Option renamed to CListOption
    MempoolReactor renamed to Reactor
    NewMempoolReactor renamed to NewReactor
    unexpose TxID method
    TxInfo.PeerID renamed to SenderID
    unexpose MempoolReactor.Mempool

Breaking changes in the state package:

[state] #2659 Mempool interface moved to mempool package
    MockMempool moved to top-level mock package and renamed to Mempool

Non Breaking changes in the node package:

[node] #2659 Add Mempool method, which allows you to access mempool

## Commits

* move Mempool interface into mempool package

Refs #2659

Breaking changes in the mempool package:

- Mempool now an interface
- old Mempool renamed to CListMempool

Breaking changes to state package:

- MockMempool moved to mempool/mock package and renamed to Mempool
- Mempool interface moved to mempool package

* assert CListMempool impl Mempool

* gofmt code

* rename MempoolReactor to Reactor

- combine everything into one interface
- rename TxInfo.PeerID to TxInfo.SenderID
- unexpose MempoolReactor.Mempool

* move mempool mock into top-level mock package

* add a fixme

TxsFront should not be a part of the Mempool interface
because it leaks implementation details. Instead, we need to come up
with general interface for querying the mempool so the MempoolReactor
can fetch and broadcast txs to peers.

* change node#Mempool to return interface

* save commit = new reactor arch

* Revert "save commit = new reactor arch"

This reverts commit 1bfceacd9d.

* require CListMempool in mempool.Reactor

* add two changelog entries

* fixes after my own review

* quote interfaces, structs and functions

* fixes after Ismail's review

* make node's mempool an interface

* make InitWAL/CloseWAL methods a part of Mempool interface

* fix merge conflicts

* make node's mempool an interface

## Description

Previously only outbound peers can be persistent.

Now, even if the peer is inbound, if it's marked as persistent, when/if conn is lost,
Tendermint will try to reconnect. This part is actually optional and can be reverted.

Plus, seed won't disconnect from inbound peer if it's marked as
persistent. Fixes #3362

## Commits

* make persistent prop independent of conn direction

Previously only outbound peers can be persistent. Now, even if the peer
is inbound, if it's marked as persistent, when/if conn is lost,
Tendermint will try to reconnect.

Plus, seed won't disconnect from inbound peer if it's marked as
persistent. Fixes #3362

* fix TestPEXReactorDialPeer test

* add a changelog entry

* update changelog

* add two tests

* reformat code

* test UnsafeDialPeers and UnsafeDialSeeds

* add TestSwitchDialPeersAsync

* spec: update p2p/config spec

* fixes after Ismail's review

* Apply suggestions from code review

Co-Authored-By: melekes <anton.kalyaev@gmail.com>

* fix merge conflict

* remove sleep from TestPEXReactorDoesNotDisconnectFromPersistentPeerInSeedMode

We don't need it actually.

Refs #3531

* execCommitBlock should not read from state.lastValidators

* fix height 1

* fix blockchain/reactor_test

* fix consensus/mempool_test

* fix consensus/reactor_test

* fix consensus/replay_test

* add CHANGELOG

* fix consensus/reactor_test

* fix consensus/replay_test

* add a test for replay validators change

* fix mem_pool test

* fix byzantine test

* remove a redundant code

* reduce validator change blocks to 6

* fix

* return peer0 config

* seperate testName

* seperate testName 1

* seperate testName 2

* seperate app db path

* seperate app db path 1

* add a lock before startNet

* move the lock to reactor_test

* simulate just once

* try to find problem

* handshake only saveState when app version changed

* update gometalinter to 3.0.0 (#3233)

in the attempt to fix https://circleci.com/gh/tendermint/tendermint/43165

also

    code is simplified by running gofmt -s .
    remove unused vars
    enable linters we're currently passing
    remove deprecated linters
(cherry picked from commit d470945503)

* gofmt code

* goimport code

* change the bool name to testValidatorsChange

* adjust receive kvstore.ProtocolVersion

* adjust receive kvstore.ProtocolVersion 1

* adjust receive kvstore.ProtocolVersion 3

* fix merge execution.go

* fix merge develop

* fix merge develop 1

* fix run cleanupFunc

* adjust code according to reviewers' opinion

* modify the func name match the convention

* simplify simulate a chain containing some validator change txs 1

* test CI error

* Merge remote-tracking branch 'upstream/develop' into fixReplay 1

* fix pubsub_test

* subscribeUnbuffered vote channel

Fixes #3585

If we are low on addresses for peering, we need to discover more peers. The
previous behavior would query existing peers; however, if an existing peer
does not participate in peer exchange, then our node will not discover more peers.

This change consults both existing peers as well as seeds when there is a deficit
in address book addresses. This allows for discovering peers though existing channels
as well as via seeds if existing peers do not share addresses.

The node.NewNode method is pretty complex at the moment, an in order to address issues like #3156, we need to simplify the interface for partial node instantiation. In some places, we don't need to build up a full node (like in the node.TestCreateProposalBlock test), but the complexity of such partial instantiation needs to be reduced.

This PR aims to eventually make this easier/simpler.

See also this gist https://gist.github.com/thanethomson/56e1640d057a26186e38ad678a1d114c for some background work done when starting to refactor here.

## Commits:

* [WIP] Refactor node.NewNode to simplify

The `node.NewNode` method is pretty complex at the moment, an in order
to address issues like #3156, we need to simplify the interface for
partial node instantiation. In some places, we don't need to build up a
full node (like in the `node.TestCreateProposalBlock` test), but the
complexity of such partial instantiation needs to be reduced.

This PR aims to eventually make this easier/simpler.

* Refactor state loading and genesis doc provider into state package

* Refactor for clarity of return parameters

* Fix incorrect capitalization of error messages

* Simplify extracted functions' names

* Document optionally-prefixed functions

* Refactor optionallyFastSync for clarity of separation of concerns

* Restructure function for early return

* Restructure function for early return

* Remove dependence on deprecated panic functions

* refactor code a bit more

plus, expose PEXReactor on node

* align logger names

* add a changelog entry

* align logger names 2

* add a note about PEXReactor returning nil

* Remove deprecated PanicXXX functions from codebase

As per discussion over
[here](https://github.com/tendermint/tendermint/pull/3456#discussion_r278423492),
we need to remove these `PanicXXX` functions and eliminate our
dependence on them. In this PR, each and every `PanicXXX` function call
is replaced with a simple `panic` call.

* add a changelog entry

Should fix #3451, #2723 and #3317.

Test TestResetTimeoutPrecommitUponNewHeight is simplified so it reduces a risk of timeout failure. Furthermore, timeout we wait for TimeoutEvents is increased, and the timeout value is more precisely computed. This should hopefully decrease a chance of non-deterministic test failures.

This assertion is problematic to ensure consistently due to dependency on scheduler. On the other hand, if I am not wrong, order in which messages are read from the channel respects order in which messages are written. Therefore, process will receive 2f+1 precommits that are not all for v (one is for nil) so TriggeredTimeoutPrecommit would be set to true. So we don't need to assert it. I know that it would be better to still assert to it but I don't know how to do it without sleep and that is ugly and is causing us nondeterministic failures.

Option to explicitly provide the -config in the testnet command, closing #3160.

* check every block appHash

Fixes #3460

Not really needed, but it would detect if the app changed in a way it
shouldn't have.

* add a changelog entry

* no need to return an error if we panic

* rename methods

* rename methods once again

* add a test

* correct error msg

plus fix a few go-lint warnings

* better panic msg

Continues from #3280 in building support for batched requests/responses in the JSON RPC (as per issue #3213).

* Add JSON RPC batching for client and server

As per #3213, this adds support for [JSON RPC batch requests and
responses](https://www.jsonrpc.org/specification#batch).

* Add additional checks to ensure client responses are the same as results

* Fix case where a notification is sent and no response is expected

* Add test to check that JSON RPC notifications in a batch are left out in responses

* Update CHANGELOG_PENDING.md

* Update PR number now that PR has been created

* Make errors start with lowercase letter

* Refactor batch functionality to be standalone

This refactors the batching functionality to rather act in a standalone
way. In light of supporting concurrent goroutines making use of the same
client, it would make sense to have batching functionality where one
could create a batch of requests per goroutine and send that batch
without interfering with a batch from another goroutine.

* Add examples for simple and batch HTTP client usage

* Check errors from writer and remove nolinter directives

* Make error strings start with lowercase letter

* Refactor examples to make them testable

* Use safer deferred shutdown for example Tendermint test node

* Recompose rpcClient interface from pre-existing interface components

* Rename WaitGroup for brevity

* Replace empty ID string with request ID

* Remove extraneous test case

* Convert first letter of errors.Wrap() messages to lowercase

* Remove extraneous function parameter

* Make variable declaration terse

* Reorder WaitGroup.Done call to help prevent race conditions in the face of failure

* Swap mutex to value representation and remove initialization

* Restore empty JSONRPC string ID in response to prevent nil

* Make JSONRPCBufferedRequest private

* Revert PR hard link in CHANGELOG_PENDING

* Add client ID for JSONRPCClient

This adds code to automatically generate a randomized client ID for the
JSONRPCClient, and adds a check of the IDs in the responses (if one was
set in the requests).

* Extract response ID validation into separate function

* Remove extraneous comments

* Reorder fields to indicate clearly which are protected by the mutex

* Refactor for loop to remove indexing

* Restructure and combine loop

* Flatten conditional block for better readability

* Make multi-variable declaration slightly more readable

* Change for loop style

* Compress error check statements

* Make function description more generic to show that we support different protocols

* Preallocate memory for request and result objects

* use dialPeer function in a seed mode

Fixes #3532

by storing a number of attempts we've tried to connect in-memory and
removing the address from addrbook when number of attempts > 16