Feature/compass grunt

This pull request adds integration for compass compiling via grunt so that it can be integrated into the build.

It adds two new tasks to grunt: grunt compass:dist for live and grunt compass:dev for local

it also adds the tasks to grunt (the default tasks) and grunt local

There is still some stuff to do though, but out of the fear of breaking stuff it hasn't been done yet. 

screen.css should be added to .gitignore
the same should also be done in booking
the compilation step should be added to the build process