* 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
* Begin simple merkle compatibility PR
* Fix query_test
* Use trillian test vectors
* Change the split point per RFC 6962
* update spec
* refactor innerhash to match spec
* Update changelog
* Address @liamsi's comments
* Write the comment requested by @liamsi
* Consistent order fields of Timestamp/BlockID fields in CanonicalVote and
CanonicalProposal
* update spec too
* Introduce and use IsZero & IsComplete:
- update IsZero method according to spec and introduce IsComplete
- use methods in validate basic to validate: proposals come with a
"complete" blockId and votes are either complete or empty
- update spec: BlockID.IsNil() -> BlockID.IsZero() and fix typo
* BlockID comes first
* fix tests
* validate reactor messages
Refs #2683
* validate blockchain messages
Refs #2683
* validate evidence messages
Refs #2683
* todo
* check ProposalPOL and signature sizes
* add a changelog entry
* check addr is valid when we add it to the addrbook
* validate incoming netAddr (not just nil check!)
* fixes after Bucky's review
* check timestamps
* beef up block#ValidateBasic
* move some checks into bcBlockResponseMessage
* update Gopkg.lock
Fix
```
grouped write of manifest, lock and vendor: failed to export github.com/tendermint/go-amino: fatal: failed to unpack tree object 6dcc6ddc143e116455c94b25c1004c99e0d0ca12
```
by running `dep ensure -update`
* bump year since now we check it
* generate test/p2p/data on the fly using tendermint testnet
* allow sync chains older than 1 year
* use full path when creating a testnet
* move testnet gen to test/docker/Dockerfile
* relax LastCommitRound check
Refs #2737
* fix conflicts after merge
* add small comment
* some ValidateBasic updates
* fixes
* AppHash length is not fixed
* crypto/merkle: Remove byter in favor of plain byte slices
This PR is fully backwards compatible in terms of function output!
(The Go API differs though) The only test case changes was to refactor
it to be table driven.
* Update godocs per review comments
* use increment and decrement operators.
* remove unnecessary else branches.
* fix package comment with leading space.
* fix receiver names.
* fix error strings.
* remove omittable code.
* remove redundant return statement.
* Revert changes (code is generated.)
* use cfg as receiver name for all config-related types.
* use lsi as the receiver name for the LastSignedInfo type.
