Fix header navigation on smaller screens

Decided to fix this issue which has been around for a while

# What's changed

* re-arranged the top nav bar things so that they're not broken anymore. Fixed the search bar so that it's responsive. Not perfect yet, but now it's a matter of styling.
![screenshot 2014-11-30 17 21 50](https://cloud.githubusercontent.com/assets/485583/5237430/91bd2ac2-78b5-11e4-8701-419c5ab6bcbd.png)
![screenshot 2014-11-30 17 21 39](https://cloud.githubusercontent.com/assets/485583/5237432/9372825e-78b5-11e4-94c3-151487043070.png)

# What's next
* Continuing to build out the create guide flow. Getting places!