Add MixinHandler specs
Add MixinHandler specs

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