Added new API to the FlowManager, that will be called
by the FlowProgrammer when a Flow Entry in the switch expires:

  FlowManager.flowEntryOnSwitchExpired(FlowEntryId flowEntryId)

The method is not implemented yet.
diff --git a/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowManager.java b/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowManager.java
index 04cde1d..8414e68 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowManager.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowManager.java
@@ -449,6 +449,15 @@
     }
 
     /**
+     * Inform the Flow Manager that a Flow Entry on switch expired.
+     *
+     * @param flowEntryId the Flow Entry ID of the expired Flow Entry.
+     */
+    public void flowEntryOnSwitchExpired(FlowEntryId flowEntryId) {
+	// TODO: Not implemented yet
+    }
+
+    /**
      * Push modified Flow Entries to switches.
      *
      * NOTE: Only the Flow Entries to switches controlled by this instance