* bound mempool memory usage

Closes #3079

* rename SizeBytes to TxsTotalBytes

and other small fixes after Zarko's review

* rename MaxBytes to MaxTxsTotalBytes

* make ErrMempoolIsFull more informative

* expose mempool's txs_total_bytes via RPC

* test full response

* fixes after Ethan's review

* config: rename mempool.size to mempool.max_txs

https://github.com/tendermint/tendermint/pull/3248#discussion_r254034004

* test more cases

https://github.com/tendermint/tendermint/pull/3248#discussion_r254036532

* simplify test

* Revert "config: rename mempool.size to mempool.max_txs"

This reverts commit 39bfa36961.

* rename count back to n_txs

to make a change non-breaking

* rename max_txs_total_bytes to max_txs_bytes

* format code

* fix TestWALPeriodicSync

The test was sometimes failing due to processFlushTicks being called too
early. The solution is to call wal#Start later in the test.

* Apply suggestions from code review

* make govet linter pass

Refs #3262

* close PipeReader and check for err

As per conversation here: https://github.com/tendermint/tendermint/pull/3218#discussion_r251364041

This is the result of running the following code on the repo:

```bash
find . -name '*.go' | grep -v 'vendor/' | xargs -n 1 goimports -w
```

* Validating that there are txs in the query results before loop throught the array

* Created tests to validate the error has been fixed

* Added comments

* Fixing misspeling

* check if the variable "skipCount" is bigger than zero. If it is not, we set it to 0. If it, we do not do anything.

* using function that validates the skipCount variable

* undo Gopkg.lock changes

Modify lookForHeight to return a height only there's a equal operator.
Previously, it was returning a height even for range conditions: "height
< 10000".

Fixes #2759

* first commit

finalize rebase

add protoc_merkle to Makefile

* in progress

* fix kvstore

* fix tests

* remove iavl dependency

* fix tx_test

* fix test_abci_cli

fix test_apps

* fix test_apps

* fix test_cover

* rm rebase residue

* address comment in progress

* finalize rebase

Refs #2051

See ADR 020: Limiting txs size inside a block docs/architecture/adr-020-block-size.md

Refs #2035

This reverts commit d02c5d1e30.

This reverts commit 96a3502

Refs #909

* Reformated the ResultStatus

* fix misuse of ResultStatus.

* updated changelog

* Fixed tests

* fixed rpc helper tests

* fixed rpc_tests

* fixed mock/status_test

* fixed typo

* fixed ommitempty on validatorstatus and the changelog

* fixed extra line in changelog

* Updated usage of the /status json response in tests after breaking changes

* Updated remaining tests with changes after searching the codebase for usage

* Reformated the ResultStatus

* fix misuse of ResultStatus.

* updated changelog

* Fixed tests

* fixed rpc helper tests

* fixed rpc_tests

* fixed mock/status_test

* fixed typo

* fixed ommitempty on validatorstatus and the changelog

* Updated usage of the /status json response in tests after breaking changes

* Updated remaining tests with changes after searching the codebase for usage

* rebased against develop

Refs #1367

Refs #1296

* remove accidental binary

* docs: s/Dummy&dummy/KVStore&kvstore/g

* glide update to abci

* update abci import paths

* dummy begone, hello kvstore

* RequestInitChain needs genesisBytes

* glide update

Expose it in rpc client
Move ABCIResults into tendermint/types from tendermint/state

comment out failing consensus tests for now

rewrite rpc httpclient to use new pubsub package

import pubsub as tmpubsub, query as tmquery

make event IDs constants
EventKey -> EventTypeKey

rename EventsPubsub to PubSub

mempool does not use pubsub

rename eventsSub to pubsub

new subscribe API

fix channel size issues and consensus tests bugs

refactor rpc client

add missing discardFromChan method

add mutex

rename pubsub to eventBus

remove IsRunning from WSRPCConnection interface (not needed)

add a comment in broadcastNewRoundStepsAndVotes

rename registerEventCallbacks to broadcastNewRoundStepsAndVotes

See https://dave.cheney.net/2014/03/19/channel-axioms

stop eventBuses after reactor tests

remove unnecessary Unsubscribe

return subscribe helper function

move discardFromChan to where it is used

subscribe now returns an err

this gives us ability to refuse to subscribe if pubsub is at its max
capacity.

use context for control overflow

cache queries

handle err when subscribing in replay_test

rename testClientID to testSubscriber

extract var

set channel buffer capacity to 1 in replay_file

fix byzantine_test

unsubscribe from single event, not all events

refactor httpclient to return events to appropriate channels

return failing testReplayCrashBeforeWriteVote test

fix TestValidatorSetChanges

refactor code a bit

fix testReplayCrashBeforeWriteVote

add comment

fix TestValidatorSetChanges

fixes from Bucky's review

update comment [ci skip]

test TxEventBuffer

update changelog

fix TestValidatorSetChanges (2nd attempt)

only do wg.Done when no errors

benchmark event bus

create pubsub server inside NewEventBus

only expose config params (later if needed)

set buffer capacity to 0 so we are not testing cache

new tx event format: key = "Tx" plus a tag {"tx.hash": XYZ}

This should allow to subscribe to all transactions! or a specific one
using a query: "tm.events.type = Tx and tx.hash = '013ABF99434...'"

use TimeoutCommit instead of afterPublishEventNewBlockTimeout

TimeoutCommit is the time a node waits after committing a block, before
it goes into the next height. So it will finish everything from the last
block, but then wait a bit. The idea is this gives it time to hear more
votes from other validators, to strengthen the commit it includes in the
next block. But it also gives it time to hear about new transactions.

waitForBlockWithUpdatedVals

rewrite WAL crash tests

Task:
test that we can recover from any WAL crash.

Solution:
the old tests were relying on event hub being run in the same thread (we
were injecting the private validator's last signature).

when considering a rewrite, we considered two possible solutions: write
a "fuzzy" testing system where WAL is crashing upon receiving a new
message, or inject failures and trigger them in tests using something
like https://github.com/coreos/gofail.

remove sleep

no cs.Lock around wal.Save

test different cases (empty block, non-empty block, ...)

comments

add comments

test 4 cases: empty block, non-empty block, non-empty block with smaller part size, many blocks

fixes as per Bucky's last review

reset subscriptions on UnsubscribeAll

use a simple counter to track message for which we panicked

also, set a smaller part size for all test cases