[BUGFIX] System roles don't get a package namespace
The role change I39f335baa01fbe9b883e98e85cb1f063bbaf5744
introduced the automatic prepend of the package namespace
where the role has been defined; except for system roles
which are at the moment Anonymous and Everybody.
For ACLs, however, the package namespace has been prepended
also for the system roles. This fixes that behavior.