* adds persistence.storageClass and limits to postgress helm install

* adds new variables to the inventory

Signed-off-by: Corey Wanless <corey.wanless@wwt.com>

installer/inventory

@@ -21,6 +21,10 @@ dockerhub_base=ansible
 # kubernetes_context=test-cluster
 # kubernetes_namespace=awx
 # tiller_namespace=kube-system
+# Optional Kubernetes Variables
+# pg_persistence_storageClass=StorageClassName
+# pg_cpu_limit=1000
+# pg_mem_limit=2
 
 # Kubernetes and Openshift Install Resource Requests
 # This is the request value for a pod's "task" container, which is the container