UX overhaul to feed item search page.

r? @ngokevin @spasovski

## Screenshots

![screen shot 2014-07-24 at 12 49 22 pm](https://cloud.githubusercontent.com/assets/23885/3692280/0a0ac284-135b-11e4-9452-7cb59e6d7018.png)

![screen shot 2014-07-24 at 12 49 29 pm](https://cloud.githubusercontent.com/assets/23885/3692279/0a09adcc-135b-11e4-938f-a2e9a62d3409.png)