Update Mako lexer from Mako trunk.
Update Mako lexer from Mako trunk.

erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments,erickt/pygments