Policy.json should be defined by user

User can override and add values to policy.json by creating flat
key-value structure under ceilometer:server:policy.

Change-Id: Ifeb2dbf54b0e32eb10a58f853a05fabf930a55a4
diff --git a/.kitchen.yml b/.kitchen.yml
index c422fbe..a12d27d 100644
--- a/.kitchen.yml
+++ b/.kitchen.yml
@@ -14,6 +14,10 @@
   formula: ceilometer
   grains:
     noservices: True
+  dependencies:
+    - name: keystone
+      repo: git
+      source: https://github.com/salt-formulas/salt-formula-keystone
   state_top:
     base:
       "*":