Create a group with all GE

[LivOriona]

Create a group gathering all space managers of all workspaces.
The goal will be to limit access to the application to the general manager and space manager groups (done manually by the workspace application installer and not automatically)
At each change of role of a user to become a space manager, add or remove the corresponding user from this group:

• at the time of adding a user to the workspace,
• at the time of adding a user to a subgroup,
• at the time of changing the role of a workspace member)