Upstream this to the OAuthenticator project

[yuvipanda]

Hello! :)

I'd love for these two authenticators to be upstreamed into jupyterhub/oauthenticator as much as possible. Particularly, if there are ways to configure GenericOAuthenticator to work for this, that would be very cool. Any missing features can go upstream into GenericOAuthenticator, and you can inherit from that to make any changes you would want here. That way, you can make changes at your speed while also contributing whatever you can upstream.

If that is impossible, adding a FacebookAuthenticator to OAuthenticator is probably not a bad idea either.

P.S. I apparently asked for a JupyterHub Facebook Authenticator in 2016 :D