Enable user's grouping on the Datastore

[Francois-Werbrouck]

Context

Currently Fertiscan and Nachet allow user to upload content into their own container. However, there is a need of having different type of users and to group certain user's together. Therfore, we need to make certain changes to enable handling the containers in the DB and add a permissions and groups structure

• Create the user permission level structure #33
• Create the container structure #34
• Create the Groups structure #225