Migrate dropdown

- Moves the Dropdown views to atlas_assets.
- Bumps gem version number
- Sorts tabs by title.

![screen shot 2013-10-28 at 1 00 13 pm](https://f.cloud.github.com/assets/2559233/1421854/f6d72ed2-3ff2-11e3-9e9a-b15e8741bf4d.png)