* signer/*: golint fixes

Specifically naming and comment formatting for documentation

* signer/*: fixed naming error crashing build

* signer/*: corrected error

* signer/core: fix tiny error whitespace

* signer/rules: fix test refactor

* eth/*:golint updates for this or self warning

* eth/*: golint updates for this or self warning, pr updated per feedback

* event/*: golint updates for this or self warning

* event/*: golint updates for this or self warning, pr updated per feedback

* metrics/*: golint updates for this or self warning

* metrics/*: golint updates for this or self warning, updated pr from feedback

* rpc/*: golint error with context as last parameter

* Update json.go

clef: documentation about setup

build: Add ldflags "-s -w" when building aar

Smaller size on mobile is always good.
Might also solve our maven central upload problem

cmd/evm: use block number from genesis

core: ensure local transactions aren't discarded as underpriced

This fixes an issue where local transactions are discarded as
underpriced when the pool and queue are full.

vendor: Fix index out of range panic when size is bigger than 1 TiB

travis.yml: remove obsolete brew-cask install

core, eth: fix tracer dirty finalization

Indicate that --light and --fast options are replaced by --syncmode

* cmd/geth, mobile: add memsize to pprof server

This is a temporary change, to be reverted before the next release.

* cmd/geth: fix variable name

Dockerfile: revert the user change PR that broke all APIs