Gruntfile.js: minor refactoring.
Gruntfile.js: minor refactoring.

charaplessa/uncss,cantyjeffrey/uncss,charaplessa/uncss,pingjiang/uncss,Renji/uncss,giakki/uncss,Renji/uncss,webdev1001/uncss,pingjiang/uncss,SteveGriffith/uncss,sdgdsffdsfff/uncss,rafaelducati/uncss,giakki/uncss,TheNotary/uncss,SteveGriffith/uncss,cantyjeffrey/uncss,webdev1001/uncss,joecritch/uncss,rafaelducati/uncss,sdgdsffdsfff/uncss,TheNotary/uncss,joecritch/uncss