Support more auth providers

[deg]

Support all the auth providers handled by Firebase. In particular, phone number authentication is very convenient on mobile apps. See https://firebase.google.com/docs/auth/web/phone-auth

[wneirynck]

I just opened a PR for email authentication. If I have time, I can try adding phone auth as well.

[deg]

Thanks! It would be great if you can get phone auth working too.

[deg]

@wneirynck's email auth PR was merged in last month. Still looking for someone to do phone and other auth providers.