Open DOVE: DCS config version not incrementing

If the last configuration on the DMC is a delete, then that config version is not reported by the DCS. It appears as if the DCS is stuck when it's state is viewed by the Open DOVE controller.

Analysis:
Since a DELETE operation doesn't have a JSON body, the config version cannot be embedded in the body so the config version isn't communicated to the DCS node which handles the request. Instead on DELETE operations, if the nodes successfully perform the operation, we should increment the cluster version automatically instead of waiting for the relevant nodes to increment it.