Replace FOFLess use with JLess wrapping lessc library

As part of decoupling the core CMS from FOF, this PR breaks the dependency on FOF's LESS classes.  FOF had implemented the lessc library by inlining its code into classes for proper code styling.  Replacing it is JLess which extends the base lessc class.  The full lessc library is included as a third party library here to enable easier updating of the library when able.

All of the FOF classes are flagged `@deprecated` and modified to extend their lessc counterparts except for FOFLess and FOFLessFormatterJoomla, which now extend their JLess counterparts.

To test this, one should verify that the Template Manager still correctly compiles LESS files or the `build/generatecss.php` CLI script still functions.  Also, if there are third parties using the FOFLess classes, those should still function correctly.

JoomlaCode: http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=33607&start=0