Add quickstart sample for private AKS cluster with custom DNS

quickstart/301-aks-private-cluster/output.tf

@@ -0,0 +1,7 @@
+output "kube_config" {
+  value = "${azurerm_kubernetes_cluster.k8s.kube_config_raw}"
+}
+
+output "host" {
+  value = "${azurerm_kubernetes_cluster.k8s.kube_config.0.host}"
+}