Propagate admin access to all apps for dashboard admins

For the context see also #61 (closed)

We need to handle dashboard admins specially so they have admin access to all apps by default, also when adding more apps. So for dashboard admins it should not be configurable which access they have to apps because they automatically grant admin access to all apps (the access menues shold be greyed out and should show "Admin".

Edited by Arie Peterson
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