title.gettext by owner without authentication if DKIM signature OK

is_owner([listname],[sender])  smtp           -> request_auth
is_owner([listname],[sender])  dkim,md5,smime -> do_it
is_listmaster([sender])        smtp           -> request_auth
is_listmaster([sender])        dkim,md5,smime -> do_it
true()                         smtp,dkim,md5,smime -> reject(reason='del_owner')	

