Add vim-less.

I've been carrying most of this around for 6 months or so now.  I don't know if you've thought about using LessCSS at all, but it's really nice: http://lesscss.org/

There are other plugins out there that do similar things, but they don't seem to work quite as nice as this one.  And one or two of them seem to think you want to recompile every time you save.  I don't like that. :-)  So this one wins!