allow for configurable openstack storage class

roles/kubernetes-apps/persistent_volumes/openstack/defaults/main.yml

 ---
 persistent_volumes_enabled: false
+storage_classes:
+  - name: standard
+    is_default: true
+    parameters:
+      availability: nova

roles/kubernetes-apps/persistent_volumes/openstack/tasks/main.yml

 ---
 - name: Kubernetes Persistent Volumes | Lay down OpenStack Cinder Storage Class template
   template:
-    src: "{{item.file}}"
-    dest: "{{kube_config_dir}}/{{item.file}}"
-  with_items:
-    - {file: openstack-storage-class.yml, type: StorageClass, name: storage-class }
+    src: "openstack-storage-class.yml.j2"
+    dest: "{{kube_config_dir}}/openstack-storage-class.yml"
   register: manifests
   when:
     - inventory_hostname == groups['kube-master'][0]
 
 - name: Kubernetes Persistent Volumes | Add OpenStack Cinder Storage Class
   kube:
-    name: "{{item.item.name}}"
+    name: storage-class
     kubectl: "{{bin_dir}}/kubectl"
-    resource: "{{item.item.type}}"
-    filename: "{{kube_config_dir}}/{{item.item.file}}"
+    resource: StorageClass
+    filename: "{{kube_config_dir}}/openstack-storage-class.yml"
     state: "latest"
-  with_items: "{{ manifests.results }}"
   when:
     - inventory_hostname == groups['kube-master'][0]
+    - manifests.changed

roles/kubernetes-apps/persistent_volumes/openstack/templates/openstack-storage-class.yml → roles/kubernetes-apps/persistent_volumes/openstack/templates/openstack-storage-class.yml.j2

+{% for class in storage_classes %}
 ---
 kind: StorageClass
 apiVersion: storage.k8s.io/v1
 metadata:
-  name: standard
+  name: "{{ class.name }}"
   annotations:
-    storageclass.kubernetes.io/is-default-class: "true"
+    storageclass.kubernetes.io/is-default-class: "{{ class.is_default | default(false) }}"
 provisioner: kubernetes.io/cinder
 parameters:
-  availability: nova
+{% for key, value in (class.parameters | default({})).items() %}
+  "{{ key }}": "{{ value }}"
+{% endfor %}
+{% endfor %}