Include Devise for IPO authentication:

**Please make sure to run 'bundle install', migrations and restart your server**

Summary: 
  - Adapt devise to work with Refinery and IPO, so now there's only one authentication framework used by:
     - IPO Login model: So the students and field hosts project can be authenticated
     - Refinery::User: The default authentication model used by Refinery::CMS
  - Include devise views: I had to change the devise routes to be more specific (p.e. `session_path` to `login_session_path`). I didn't change all the devise routes just the ones need it to make a new registration and the sessions to work properly
  - Include StudentFormApplication (WIP)