Delay DB updates until all policies processed

Delay DB updates until all policies processed

If an exception is thrown in the middle of processing policies, it's
possible for the DB to reflect a partial deployment.  This change
queues the DB changes so that they're all made at once, after all
policies have been processed.
Extracted sort() into a common place.
Corrected some comments.
Simplified the list retrieval in the junits since all DB creates and
updates are now batched together into one operation each.

Change-Id: I835175fc16d4042c741d36ec69caa8f603d46d5a
Issue-ID: POLICY-1542
Signed-off-by: Jim Hahn <jrh3@att.com>