Extend template to set up additional values:

- use_cow_images
- force_raw_images
- snapshot_image_format
- images_type

Prod-Related: PROD-34639
Change-Id: I172e8e7d97786f059dad4586d3bf27fa86b89dce
diff --git a/README.rst b/README.rst
index ce885a6..845b30a 100644
--- a/README.rst
+++ b/README.rst
@@ -33,6 +33,10 @@
         vif_plugging_timeout: 300
         vif_plugging_is_fatal: false
         instance_build_timeout: 600
+        use_cow_images: False
+        force_raw_images: True
+        snapshot_image_format: qcow2
+        images_type: default
         concurrency:
           lock_path: '/var/lib/nova/tmp'
         consoleauth: