Resources - browse by category

The local resources page has been rebuilt to allow for browsing by category. Here's a screenshot:

![screen shot 2013-12-02 at 3 59 34 pm](https://f.cloud.github.com/assets/919583/1659081/0c046958-5b9d-11e3-91b5-60b2cb3a77ac.png)

This pull request includes:
* updated Purple Binder import task (including categories)
* updated Readme on importing data for the first time (including Purple Binder)
* refactoring of resources page
* ability to browse resources by category
* ability to switch between map and list views (similar to Connect Chicago)
* using font-awesome for icons

Resolves #107, #111 and #113