core: added a mechanism to associate short names to namespaces:

- new internal registerNamespace can be used by a plugin to associate a short name to a namespace
- new NamespacesGet bridge method retrieve those associations

frontends/src/bridge/dbus_bridge.py

@@ -504,6 +504,20 @@ class Bridge(object):
             error_handler = lambda err:errback(dbus_to_bridge_exception(err))
         return self.db_core_iface.messageSend(to_jid, message, subject, mess_type, extra, profile_key, timeout=const_TIMEOUT, reply_handler=callback, error_handler=error_handler)
 
+    def namespacesGet(self, callback=None, errback=None):
+        if callback is None:
+            error_handler = None
+        else:
+            if errback is None:
+                errback = log.error
+            error_handler = lambda err:errback(dbus_to_bridge_exception(err))
+        kwargs={}
+        if callback is not None:
+            kwargs['timeout'] = const_TIMEOUT
+            kwargs['reply_handler'] = callback
+            kwargs['error_handler'] = error_handler
+        return self.db_core_iface.namespacesGet(**kwargs)
+
     def paramsRegisterApp(self, xml, security_limit=-1, app='', callback=None, errback=None):
         if callback is None:
             error_handler = None