Install doorkeeper

Doorkeeper implements an OAuth 2 provider.
Configure doorkeeper

Doorkeeper has been configured to use Active Record as its ORM, authenticate users using Warden, and allow all applications without authorization.
Run doorkeeper migrations

Doorkeeper requires a few tables to save applications and tokens in it. Those have been created.
Generate doorkeeper views

Doorkeeper's views need to be customized at one point or another, so they have been generated to be present in the project's source.
Merge branch 'feature/doorkeeper' into develop
Add user factory

The user factory builds/creates a new user object that can be used to verify the correct behavior of devise and doorkeeper.
Configure RSpec to include support directory

Factory Girl's configuration and a custom matcher are placed in the support directory, and that won't be all (probably). Therefore, we want to include it by default.
Implement User specs

The user model consists only of devise modules, so its not absolutely necessary to write specs for it. But to give the user a better feeling, we have included specs that verify the most important behavior of the user model.
Merge branch 'feature/specs' into develop