Bootstrap 3

__Notes:__
- If sprockets fails or the styles look really messed up, you may need to delete your `tmp` directoy (the one in the Alexandria repo) and/or restart your Rails server.
- The typeahead plugin in Bootstrap 2 (that we are currently using) is now removed in Bootstrap 3. We will need to transition to [typeahead.js](https://github.com/twitter/typeahead.js), which I did not do yet.
- I am currently using `col-md-*` for all of our column tiers. We may want to use different tiers in different places in the future.