refactor cmd/config to internal

cmd/config/internal/commands/test/override.yaml

@@ -0,0 +1,15 @@
+# Copyright 2019 The Kubernetes Authors.
+# SPDX-License-Identifier: Apache-2.0
+
+
+
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: test
+spec:
+  template:
+    spec:
+      containers:
+      - name: test
+        image: nginx:v1.9