process_updates: don't report empty Contact: header when request unregistered all contacts. unregister_contact: only unregister dynamic contacts.
process_updates: don't report empty Contact: header when request
unregistered all contacts.
unregister_contact: only unregister dynamic contacts.


git-svn-id: 3f662d0c7823f96a484d6a9a7c90f2d7866b6747@936 e454d3dc-12ff-0310-9b8b-94264392205f

bernardd/yxa,bernardd/yxa,bernardd/yxa,bernardd/yxa