fixed bracketing and initialized recess module to make RECESS work

According to the bug https://bugzilla.mozilla.org/show_bug.cgi?id=982188 LESS linting for Goggles project wasn't performing correctly. To reproduce it, you have to execute 'grunt' in Googles directory. It was showing "0 files lint free". In order to fix it file Gruntfile.js had to be updated to initialize RECESS module which does the LESS linting and fix bracketing. Now it works and shows errors in *.less files.