Device Anti-Entropy

- create Advertisement
- handler for Advertisement
- register handler, background thread to send advertisement

Change-Id: I99e8a7d68747970c34b3c25c6d0489769d251446
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/serializers/ClusterMessageSerializer.java b/core/store/dist/src/main/java/org/onlab/onos/store/serializers/ClusterMessageSerializer.java
index c0cefd6..e20b4a6 100644
--- a/core/store/dist/src/main/java/org/onlab/onos/store/serializers/ClusterMessageSerializer.java
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/serializers/ClusterMessageSerializer.java
@@ -35,4 +35,4 @@
         byte[] payload = input.readBytes(payloadSize);
         return new ClusterMessage(sender, subject, payload);
     }
-}
\ No newline at end of file
+}