This update addresses the following:
1.  Decouple the kafka messaging proxy from the kafka client.  This
will allow us to try out different kafka clients as well as test
the client separately.
2. Create unique device topics for the core, olt adapter and onu
adapters.  This will ensure only cores and adapters handling these
devices will listens to the device messages.
3. Update the core with the latest device model APIs and changes.
While most of the model issues have been fixed, there is still an
issue with updating a child branch.   This will be dealt in a separate
update.

Change-Id: I622ef5c636d7466bb3adefaa4ac4c85d7c450bea
diff --git a/db/model/root.go b/db/model/root.go
index a05fbdd..c4339a4 100644
--- a/db/model/root.go
+++ b/db/model/root.go
@@ -48,7 +48,7 @@
 	Loading       bool
 	RevisionClass interface{}
 
-	mutex    sync.RWMutex
+	mutex sync.RWMutex
 }
 
 // NewRoot creates an new instance of a root object
@@ -116,12 +116,12 @@
 	for len(r.Callbacks) > 0 {
 		callback := r.Callbacks[0]
 		r.Callbacks = r.Callbacks[1:]
-		callback.Execute(nil)
+		go callback.Execute(nil)
 	}
 	for len(r.NotificationCallbacks) > 0 {
 		callback := r.NotificationCallbacks[0]
 		r.NotificationCallbacks = r.NotificationCallbacks[1:]
-		callback.Execute(nil)
+		go callback.Execute(nil)
 	}
 }