Initial implementation of XMPP Publish/Subscribe

Change-Id: I9930056b83004fa7a085f72f63ba973f9ec2d95b
diff --git a/modules.defs b/modules.defs
index f574d9d..555e32d 100644
--- a/modules.defs
+++ b/modules.defs
@@ -253,6 +253,7 @@
     '//protocols/p4runtime:onos-protocols-p4runtime-oar',
     '//protocols/gnmi:onos-protocols-gnmi-oar',
     '//protocols/xmpp/core:onos-protocols-xmpp-core-oar',
+    '//protocols/xmpp/pubsub:onos-protocols-xmpp-pubsub-oar',
 ]
 
 MODELS = [