Initial work on adding groups to the less files.
Added the rewrite, should now properly added the groups functionality, defaults to 'default' group. It is recommended to use the layout handle for the group.
Updated the README with clearer examples.
Revert "Updated lessphp"

This reverts commit df0f9e2bfa63068b819d0ffbc47f9bf0b3647f72.
made the default nogroup, updated readme and added better comment to configuration setting
Merge pull request #11 from ho-nl/groups

Added grouping functionality