Add ability to catch policy from mines based on compound targets

Related-Prod: PROD-31956
Change-Id: I848d5d202924ff664aff60498d3a23281e21b8cb
diff --git a/README.rst b/README.rst
index 7e52bf4..082d435 100644
--- a/README.rst
+++ b/README.rst
@@ -96,6 +96,13 @@
             name: keystone_policy.json
             grain_name: keystone_policy
             enabled: true
+          dns:
+            enabled: True
+            source: 'mine'
+            target_type: 'compound'
+            host: 'I@designate:server'
+            grain_name: 'designate_policy'
+            name: 'designate_policy.json'
           compute:
             source: file
             name: nova_policy.json