Add missing fonts thanks to Typekit

I don't know if there is any "branding" requirements for this, but typography was broken. 
The fonts `proxima-nova` and `kulturista` were set in scss styles, but not available.
I added those to a TypeKit account for RuLu.
After:
![screen shot 2014-04-20 at 17 39 49](https://cloud.githubusercontent.com/assets/224928/2750880/fa3ed9ce-c8a2-11e3-921a-81918d938472.png)

Before:
![screen shot 2014-04-20 at 17 45 19](https://cloud.githubusercontent.com/assets/224928/2750881/fede3970-c8a2-11e3-84ae-853382d8b80c.png)