Add 2 new configuration variables to manage oauth providers

[gregmzs]

Shout it be possible to add 2 new configuration variable :

• SYNC_PROFILE_FROM_PROVIDER (default [])
• SYNC_PROFILE_ATTRIBUTES (default true, but not commented in gitlab.yml anymore)

To manage account existing in Gitlab and a new Azure Authentication.

Thanks ;)

[flavienbwk]

~Definitely, it looks necessary for Azure AD v2 configuration~

In any case it is useful, I have been able to configure my Azure binding this way and without these parameters : https://github.com/flavienbwk/gitlab-azure-oauth/blob/d766545776ce2662832a43f4731e745fc8950f6c/docker-compose.example.yml#L103