*: remove TODO.md file

This existed for when we were developing v2 but v1 was using the
issue tracker. We've since moved these goals to the issue tracker.

TODO.md

-TODOs in no particular order
-
-OpenID Connect / OAuth2
-
-- [ ] Let clients require signing algorithms (see id_token_signed_response_alg)
-- [ ] Support ECDSA keys
-- [ ] Support client_secret_jwt client authentication
-- [ ] Add a "NextSigningKey" to the storage.Keys type so clients can cache more aggressively
-- [ ] Support grant_type=password
-
-Connectors
-
-- [ ] Port BitBucket connector
-- [ ] Port UAA connector
-- [ ] Simplify LDAP connector configuration
-- [ ] Create proposal for a minimal "local" connector implementation
-
-User self-management
-
-- [ ] Implement the user object proposal
-- [ ] Provide user profile page
-- [ ] Let user's merge accounts when they have multiple remote identities
-- [ ] Let user's revoke clients with refresh tokens
-
-Documentation
-
-- [ ] Describe motivation for a V2
-- [ ] Add OpenID Connect client library suggestions
-- [ ] Add getting started guide
-- [ ] Add more connector documentation
-  - [ ] Include instructions for getting client credentials for upstream provider
-- [ ] Improve Kubernetes documentation and include client auth provider docs
-
-Storage
-
-- [x] Add SQL storage implementation
-- [ ] Utilize fixes for third party resources in Kubernetes 1.4 
-
-UX
-
-- [ ] Add 500 and 404 pages
-- [ ] Add an OBB template
-- [ ] Set an HTTP cookie so users aren't constantly reprompted for passwords
-- [ ] Add proposal for letting others style existing HTML templates
-- [ ] Support serving arbitrary static assets
-
-Backend
-
-- [ ] Improve logging, possibly switch to logrus
-- [ ] Standardize OAuth2 error handling