Integrates OAuth

Adds library to facilitate oauth dance and acquire token.

Includes middleware to detect when new token is needed, method to get token or dispatch request to middleware, code to handle both sides of the oauth request, and database model to store tokens.

Depends on django's auth-middleware

@kyfantaz 
Since you've played around with the admin, can you confirm that the admin is a project-level url and that individual apps don't have their own unique admins?  I think this is the case, but it would be good to have one of you guys verify.