Auth retrieval (GET)

The following sequence describes the authentication and role retrieval:

1. Look-up the user in the OpenLDAP directory (with a configurable service user):

   Currently, this will be cn=Manager,dc=stoney-cloud,dc=org

   Later on, this will be a service user.

2. If the user exists, try to bind with the users credentials.
3. If the bind was successful, retrieve the users roles with the service user.