title.gettext add performed by list owner does not need authentication

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