Major updates
- Update OAuth2.0 version from draft30 to final spec (RFC6749).
- Add Client types support.
- Support multiple redirection URIs.
- Revise the architecture for tokens, clients, and users management.
- Memory and MongoDB implementations.
- Client-side implementations are removed temporary. (Not supported at this time.)
- Fix the license informations.

Token Endpoint:
- Ensure that the requested grant type is allowed for the client.
- Add support for client type.
- Fix the token response. (token_type, scope)
Updates for 'authorization_code' flow:
- Ensure that the authorization code was issued to the client.
- Add 'redirect_uri' validation.
Updates for 'client_credentials' flow:
- Implement the 'client_credentials' flow.

Authorization Endpoint:
- Fix the 'POST' method support.
- Add session timout support.
- Fix the session management bugs.
- Allow clients to send multiple response types.
- Ensure that the requested response type is allowed for the client.
- Fix the issue that 'state' was actually not managed.
- Update the recirect_uri handling. (Dynamic Configuration)

Client Management:
- Revise ClientStore to ClientManager.
- Remove client_id and client_secret from #createClient method. (These parameters should provided from AuthServer.)

Token Management:
- Remove TokenGenerator, replaced with TokenManager.
- Support token management suitable for RFC6749.

User Management:
- Add UserManager for Resource Owner Password Credentials.