Feature: Enable login using external user database

The OpenID Connect server might have used a different user backed to authenticate users. For example LDAP. In that case the user is created during the authentication process. However application permissions might not have been set yet so the user can not log in to any application.

To solve this each application should have a "default" flag, that implicitly allows access to the application for each user

Todos:

• Handle empty passwords as users might not have set a password yet.
• Make login ID unique as users can now be updated and might have been created externally
• Add default field to application
• Add GUI element to make an application a default application