* Tweaks to the policy model
* InheritanceUtils implements inheritance of tenants to generate a normalized
  representation
* Beginnings of renderer common.  Implement resolution of policies into a
  policy cache that can be queried against and we can add subscriptions.

Change-Id: Ia74f4adc4a4dddd43c7ffff3189cacb3fa69bb51
Signed-off-by: Rob Adams <readams@readams.net>