Minor changes for ghosts, added verb to remain anonymous

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The aghost verb is in most of the admin_verbs_* lists, and itself it only checks for 'holder'. That made me think that all holders have (and should have) this accessible. Is there any way to check if the user has the right for it? Considering the permission system is all over the place without proper rights checks in many places and without actual nice system to handle permissions and assigning verbs and procs to permission groups it's kind of hard to handle this one I believe.