refactoring FlowProgrammer and FlowSync, adding flow removed listener, and encorporating Pavlin's comment
diff --git a/src/main/java/net/onrc/onos/ofcontroller/flowprogrammer/IFlowSyncService.java b/src/main/java/net/onrc/onos/ofcontroller/flowprogrammer/IFlowSyncService.java
index 1e71f6a..2b9d51d 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/flowprogrammer/IFlowSyncService.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/flowprogrammer/IFlowSyncService.java
@@ -10,4 +10,6 @@
  */
 public interface IFlowSyncService extends IFloodlightService {
     public void synchronize(IOFSwitch sw);
+    
+    public void interrupt(IOFSwitch sw);
 }