XEP: updated privileged entity according to discussions following the council's veto (see http://mail.jabber.org/pipermail/standards/2014-December/029378.html): - Big simplification and restriction following council's veto and standard@ discussions - Configuration is not done only on server own configuration - No more client mode - Permissions are adverised using <message/> - The only <iq/> privilege still available is jabber:iq:roster