feat: Watch OpenSergo CRD actively in Istio environment #37
Description
In Istio environment, we need an extra watcher to watch OpenSergo CRDs actively, so we can know the change of OpenSergo CRDs such as TrafficRouter and etc. When the OpenSergo CRDs in Istio environment are changed, we may transfer them into Istio CRDs and apply them in K8s cluster.