Integrate Ego into ICGC Portal

[Fgerthoffert]

• [ ] Finish Ego (overture-stack/ego#188)
• [ ] Finish Daco2Ego (https://github.com/icgc-dcc/roadmap/issues/7)
• [ ] QA environment setup (https://github.com/icgc-dcc/roadmap/issues/9)
• [ ] Add remaining functions for Ego Admin UI
  • [ ] Add policies and assign permissions to users/groups
  • [ ] List and revoke user tokens
• [ ] Portal changes & token management
  • [ ] UI changes for login
  • [x] Additional endpoints to integrate with Portal UI
  • [ ] Set up all redirects and API calls to EGO

https://docs.google.com/document/d/1hEdSoYUF5FKK4vCYAqT2ug670Kf0gppiEU14M4tWsfI/edit