Updating readme based on new flag for webhook

* Adding volumesnapshotclasses to admission configuration template

README.md

@@ -109,6 +109,8 @@ Read more about how to install the example webhook [here](deploy/kubernetes/webh
 
 * `--port`: Secure port that the webhook listens on (default 443)
 
+* `--kubeconfig <path>`: Path to Kubernetes client configuration that the webhook uses to connect to Kubernetes API server. When omitted, default token provided by Kubernetes will be used. This option is useful only when the snapshot controller does not run as a Kubernetes pod, e.g. for debugging.
+
 ### Distributed Snapshotting
 
 The distributed snapshotting feature is provided to handle snapshot operations for local volumes. To use this functionality, the snapshotter sidecar should be deployed along with the csi driver on each node so that every node manages the snapshot operations only for the volumes local to that node. This feature can be enabled by setting the following command line options to true:

deploy/kubernetes/webhook-example/admission-configuration-template

@@ -8,7 +8,7 @@ webhooks:
   - apiGroups:   ["snapshot.storage.k8s.io"]
     apiVersions: ["v1", "v1beta1"]
     operations:  ["CREATE", "UPDATE"]
-    resources:   ["volumesnapshots", "volumesnapshotcontents"]
+    resources:   ["volumesnapshots", "volumesnapshotcontents", "volumesnapshotclasses"]
     scope:       "*"
   clientConfig:
     service: