Fix node-sass problems

I had to head away yesterday but looks like there were some problems with using node-sass instead of ruby sass.

This

* places all included files in an includes folder. This lets the file we want be the one that is compiled. Not sure why only the fonts file was being compiled and why we need this but it does solve the problem.
* Removed font-path() which was a rails helper
* Removed all % sass placeholder selectors. Can't use them in node-sass.