I've finally started to rethink the database structure. The goal I'm trying to reach: only use User objects to manage permissions and accesses to the webui and associate other objects to them if needed (like mailboxes).
see #105
We add an intermediate role : Reseller. It is somewhere between a super administrator and a domain administrator. A reseller can create objects (a limited or not amount) and then define permissions on those objects:
* Create a domain admins,
* Assign limits to those admins,
* ...
see #105
Antoine Nguyen