[VOL-1564] Refactor flow deletion

This update consists of the following:
1)  Refactor the flow management around flow deletion and
addition.
2) Update the simulated adapters to receive and do initial
processing of flow updates (bulk and incremental)
3) Add more tests to the flow utils test suite
4) Add a new flow management test for integration test in a
development environment (work in progress)

Change-Id: I9dbb2adf9e600af52ce267b727617be181c8f1ab
diff --git a/rw_core/core/device_manager.go b/rw_core/core/device_manager.go
index faf8da8..f52345e 100755
--- a/rw_core/core/device_manager.go
+++ b/rw_core/core/device_manager.go
@@ -592,8 +592,22 @@
 	log.Debugw("addFlowsAndGroups", log.Fields{"deviceid": deviceId})
 	if agent := dMgr.getDeviceAgent(deviceId); agent != nil {
 		return agent.addFlowsAndGroups(flows, groups)
-		//go agent.addFlowsAndGroups(flows, groups)
-		//return nil
+	}
+	return status.Errorf(codes.NotFound, "%s", deviceId)
+}
+
+func (dMgr *DeviceManager) deleteFlowsAndGroups(deviceId string, flows []*ofp.OfpFlowStats, groups []*ofp.OfpGroupEntry) error {
+	log.Debugw("deleteFlowsAndGroups", log.Fields{"deviceid": deviceId})
+	if agent := dMgr.getDeviceAgent(deviceId); agent != nil {
+		return agent.deleteFlowsAndGroups(flows, groups)
+	}
+	return status.Errorf(codes.NotFound, "%s", deviceId)
+}
+
+func (dMgr *DeviceManager) updateFlowsAndGroups(deviceId string, flows []*ofp.OfpFlowStats, groups []*ofp.OfpGroupEntry) error {
+	log.Debugw("updateFlowsAndGroups", log.Fields{"deviceid": deviceId})
+	if agent := dMgr.getDeviceAgent(deviceId); agent != nil {
+		return agent.updateFlowsAndGroups(flows, groups)
 	}
 	return status.Errorf(codes.NotFound, "%s", deviceId)
 }