* Implement Azure AD oauth

* Use go-jose and cleanup

* Update go-jose in go.mod

* cleanup

* Add unit tests

* Fix scopes

* Add documentation page

* Improve documentation

* Convert extract_role into function.

* Do not use upn and replace unique_name with preferred_username

* Configure login button

* Use official microsoft icon and color from branding guideline.

* Add Azure AD config section in sample.ini.