Improve authentication by adding OAuth 2.0 and OpenID Connect

[fv3rdugo]

Actually Ravada allow local users in DB, LDAP and SSO/CAS as authentication protocol.
It might be a good idea to add OpenID Connect. It's an interoperable authentication protocol based on the OAuth 2.0 framework of specifications (IETF RFC 6749 and 6750).
Consider implementing it as module in Apache or coding it in the backend.

Some information about it:
https://openid.net/
https://github.com/OpenIDC/mod_auth_openidc