LessCSS 1.4.0 import support (WIP)

This is the beginnings of work into getting two new features of lesscss into lessphp: (less) and media queries on import. This covers a few issues like https://github.com/leafo/lessphp/issues/350.

@import (css) "bootstrap.less" screen and (max-width: 700px);
See: http://lesscss.org/#-importing

With the current commit, adding (less) or (css) before your import filename tells the system how to handle it. I have had little luck getting the media queries to work. My bleeding edge isn't even worth pushing, besides maybe some query parsing.

Email or message me if you wish to see the bleeding edge.