core: sendMessage triggers now use a treatments deferred;

- treaments deferred can be used by plugins to change XML elements before sending them, in a similar way as for newMessage
    - sendMessageXml trigger became useless, so it as been removed in favor of the new deferred

src/plugins/plugin_exp_parrot.py

@@ -48,7 +48,7 @@ class Exp_Parrot(object):
         host.trigger.add("MessageReceived", self.MessageReceivedTrigger, priority=100)
         #host.trigger.add("sendMessage", self.sendMessageTrigger, priority=100)
 
-    #def sendMessageTrigger(self, mess_data, profile):
+    #def sendMessageTrigger(self, mess_data, treatments, profile):
     #    """ Deactivate other triggers if recipient is in parrot links """
     #    client = self.host.getClient(profile)
     #    try: