OAuth2 integration

[timurvafin]

Would like to open discussion about integration OAuth2 in to the Rails Base API.

In case we pro dive API privately we need allow only authorized client to consume our API.
It's make sense to implement OAuth2 based protocol, so client could use their secret keys.

We need to think:

• how to work with devise
• how to work with CORS https://github.com/doorkeeper-gem/doorkeeper/wiki/%5BCORS%5D-Cross-Origin-Resource-Sharing

Preferable solutions are:

• https://github.com/doorkeeper-gem/doorkeeper
• https://github.com/doorkeeper-gem/doorkeeper/wiki
• http://railscasts.com/episodes/353-oauth-with-doorkeeper