Added rest API to look into the topology events map for debugging

Change-Id: I15f95fa7184bf6e087926c8cbc49db2dd6f65a5a
diff --git a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/TopologyManager.java b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/TopologyManager.java
index 315cee7..642a536 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/TopologyManager.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/TopologyManager.java
@@ -48,7 +48,7 @@
 	    .getLogger(TopologyManager.class);
 
     private IEventChannel<byte[], TopologyEvent> eventChannel;
-    private static final String EVENT_CHANNEL_NAME = "onos.topology";
+    public static final String EVENT_CHANNEL_NAME = "onos.topology";
     private EventHandler eventHandler = new EventHandler();
 
     private final NetworkGraphDatastore datastore;