Fix admin_only decorator in omero.cli
Fix CLI plugins to use admin_only across the board
Add integration tests to cover admin_only checks
Merge remote-tracking branch 'origin/develop' into 5137_admin_only

Conflicts:
	components/tools/OmeroPy/src/omero/plugins/ldap.py
Decorate bin/omero group add with admin_only
Merge pull request #3158 from sbesson/5137_admin_only

CLI: admin_only decorator