Enable message carbons xep-0280

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/xmppthread.py b/xmppthread.py
index 7a608e7..4edd3dd 100644
--- a/xmppthread.py
+++ b/xmppthread.py
@@ -33,7 +33,7 @@
         self.registerPlugin('xep_0085') # chat state notification
         self.registerPlugin('xep_0172') # user nick
         self.registerPlugin('xep_0199') # XMPP Ping
-        #self.registerPlugin('xep_0280') # carbons
+        self.registerPlugin('xep_0280') # carbons
 
         self['xep_0030'].add_identity(category='gateway', itype='hangouts', name='Google Hangouts Transport')