Navigation bar revamp

Simplification, beautification of the nav bar.

-Implemented new icons
-Simplified the signup/login procedure

SEARCH IS BROKEN, however, I do believe it is broken on the live site too :tongue: 

I will look into implementing @zfeuers1 code into the Bootstrap styled search bar in the next few days, maybe he can look too.

There are still some broken/unresponsive things in the header, but, you know, one thing at a time. I don't want to codebomb.