Add support for GitHub codeblocks when using RedCarpet.
Add support for GitHub codeblocks when using RedCarpet.

jreinert/yard,iankronquist/yard,alexdowad/yard,herosky/yard,jreinert/yard,alexdowad/yard,amclain/yard,herosky/yard,amclain/yard,ohai/yard,thomthom/yard,lsegal/yard,ohai/yard,alexdowad/yard,lsegal/yard,amclain/yard,lsegal/yard,iankronquist/yard,herosky/yard,thomthom/yard,ohai/yard,iankronquist/yard,jreinert/yard,thomthom/yard