Split authentication helpers out (although these should be in a module, not a Rails helper class)
Some minor cleanups - give broker a named route for rest_urls instead of doing generation directly
Expose API endpoints for authorizations, add bearer authentication checks, cleanup and simplify authentication path even more to isolate steps, and expose a few more attributes on authorization endpoints.

Conflicts:
	controller/app/controllers/authorizations_controller.rb
	controller/app/controllers/user_controller.rb
	controller/app/rest_models/rest_authorization.rb
	controller/config/initializers/doorkeeper.rb
Identity lookup based on identity _id