Docs: clarification about running checkers when aggregating errors.
Add shellcheck as zsh checker.
OCLint: minor cleanup.
cpplint: add exit code check.
Bug fix: the result of expand('<sfile>:p:h') has to be escaped.
Escape Festschrift: getExec() needs to be escaped before being used.
avr-gcc: added syntax checker
Cleanup: avrgcc checker.
Escape Festschrift, vol. 2: add function getExecEscaped().
Add support for g:syntastic_extra_filetypes.

This is useful when registering checkers outside syntastic.
Bug fix: pilot error adding g:syntastic_extra_filetypes.
added syntax checking for .asm and .s files using gcc
Cleanup: asm/gcc checker.
Cleanup: allow more exec overrides; formatting.
Vimlint: better highlighting for `l:var`.
Vimlint: add a safety net for a bug in Vim.
Attempt to shut up "go test".
Revert "Attempt to shut up "go test"."

This reverts commit c6636f6db162bebe26a9a76a6114578f03b46424.
Second attempt to shut up "go test".