Support id_token as a response type
https://www.pivotaltracker.com/story/show/81117398
[#81117398]
https://www.pivotaltracker.com/story/show/81118314
[#81118314]
Password flow completed
Implicit (direct) flow completed
Authorization Flow completed
Hybrid flow implemented
Hybrid flow with approval completed

Use unique user for each test
Merge branch 'feature/id_token_response_type' into develop
Update UAA to match feature set of id_token (OpenID features)