policy.json: Allow one to manage them from the puppet module

This commit allow a deployer to manage the policies via this module
It relies on augeas to change only the policy needed. The init takes
a hash of policies and apply them.

Change-Id: I398fca298330b8cc5d5d7dfbf6ebed067b34f9d7
Merge "policy.json: Allow one to manage them from the puppet module"