bt-navbar

Just sass changes. Fixes navbar issues found in https://trello.com/c/FMr8ATey/197-nav-bar-fixes. Also strips out a few seemingly unnecessary items.

![screenshot 2014-06-06 16 11 51](https://cloud.githubusercontent.com/assets/1597375/3206114/ecd7f368-edc0-11e3-93a0-76afc2a19eb0.png)