Adds a genesis parameter `initial_height` which specifies the initial block height, as well as ABCI `RequestInitChain.InitialHeight` to pass it to the ABCI application, and `State.InitialHeight` to keep track of the initial height throughout the code. Fixes #2543, based on [RFC-002](https://github.com/tendermint/spec/pull/119). Spec changes in https://github.com/tendermint/spec/pull/135.

## Description

the second part of state proto migration

Closes: #XXX

This is useful for custom state sync `StateProvider` implementations that need to build new states for bootstrapping the node. It will also be useful when implementing other mechanisms to bootstrap nodes, e.g. #4642 and #3713.

* types: change `Commit` to consist of just signatures

These are final changes towards removing votes from commit and leaving
only signatures (see ADR-25)

Fixes #1648

* bring back TestCommitToVoteSetWithVotesForAnotherBlockOrNilBlock

+ add absent flag to Vote to indicate that it's for another block

* encode nil votes as CommitSig with BlockIDFlagAbsent

+ make Commit#Precommits array of non-pointers
because precommit will never be nil

* add NewCommitSigAbsent and Absent() funcs

* uncomment validation in CommitSig#ValidateBasic

* add comments to ValidatorSet funcs

* add a changelog entry

* break instead of continue

continue does not make sense in these cases

* types: rename Commit#Precommits to Signatures

* swagger: fix /commit response

* swagger: change block_id_flag type

* fix merge conflicts

Refs #3262

* Removal of TotalTx & NumTx

- Removed totalTx and numTx

closes #2521

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

* abci proto changes

* proto number fix

* txfilter_test fix

* comments on PR

* further changes

* bring back metrics

* fix indexer

* fix TestBlockMaxDataBytes and TestBlockMaxDataBytesUnknownEvidence

* indexer service back to header

* statistics.go fix

* fix ci

* listen for blocks, not headers

to be able to record txs throughput

* fix TestNetworkNewBlock

* fix tests

* fix tests in types package

* fixes after Anton's review

* fix tests

* bring back `consensus_total_txs` metric

I mistakenly thought it was removed.

* improve changelog

* remove LastBlockTotalTx from state

* docs: remove getNumTxs from BeginBlock Java example

- rename fields, methods, comments, tests

* types: test tm2pm on fully populated header

* upgrade for amino v0.13.0-rc0

* fix lint

* comment out final test

* use types.NewValidator

* node: set p2p.ProtocolVersion from state, not globals

* abci: update RequestInfo for versions

* abci: update ResponseInfo for versions

* compile fix

* fix test

* software_version -> version

* comment fix

* update spec

* add test

* comments and fix test

* types: add Version to Header

* abci: add Version to Header

* state: add Version to State

* node: check software and state protocol versions match

* update changelog

* docs/spec: update for versions

* state: more tests

* remove TODOs

* remove empty test

* require block.Time of the fist block to be genesis time

Refs #2587:

```
We only start validating block.Time when Height > 1, because there is no
commit to compute the median timestamp from for the first block. This
means a faulty proposer could make the first block with whatever time
they want.

Instead, we should require the timestamp of block 1 to match the genesis
time.

I discovered this while refactoring the ValidateBlock tests to be
table-driven while working on tests for #2560.
```

* do not accept blocks with negative height

* update changelog and spec

* nanos precision for test genesis time

* Fix failing test (#2607)

* Pass nil to NewValidatorSet() when genesis file's Validators field is nil

Closes: #2616

* Update CHANGELOG_PENDING.md

* remove ConsensusParams.TxSize and ConsensusParams.BlockGossip

Refs #2347

* block part size is now fixed

Refs #2347

* use max data size, not max bytes for tx limit

Refs #2347

* Implement BFT time

* set LastValidators when creating state in state helper

for heights >= 2

- state.MakeBlock takes a proposerAddr
- validateBlock only checks that the ProposerAddress is in the validator
  set
- fix raceyness from bad proposer test:
  - use privValidator to get the proposer address (instead of racy
    state)
  - note we had to remove the test that checked the correct proposer was
    included for higher rounds because we don't have a good way to test
    this with multiple consensus states and not using the
    privValidator.Address while calling createProposalBlock was a hack!

Refs #1134

Validation:

- ignored in block.ValidateBasic since it's stateful information
- checked in blockExec.ValidateBlock

This reverts commit d02c5d1e30.

This reverts commit 96a3502

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

Add some tests.
Behaves like saving validator set, except it always saves at each height
instead of a reference to last changed.

State maintains LastResultsHash
Verify that we can produce unique hashes for each result,
and provide valid proofs from the root hash.