[incubator/cassandra] Update apiVersion for StorageClass (#1455)

* Update apiVersion for StorageClass

Fixes #1422

* Update Chart.yaml

incubator/cassandra/Chart.yaml

@@ -1,5 +1,5 @@
 name: cassandra
-version: 0.1.1
+version: 0.1.2
 description: Apache Cassandra is a free and open-source distributed database management system designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure. 
 icon: https://upload.wikimedia.org/wikipedia/commons/5/5e/Cassandra_logo.svg
 keywords:

incubator/cassandra/sample/create-storage-gce.yaml

@@ -1,5 +1,5 @@
 kind: StorageClass
-apiVersion: storage.k8s.io/v1beta1
+apiVersion: storage.k8s.io/v1
 metadata:
   name: generic
 provisioner: kubernetes.io/gce-pd