Refactor unit tests for encryption utility and add assertions
Refactor unit tests for encryption utility and add assertions

Also, re-add the instance variables that were removed from
DBAPICryptParamsPropsTest in 4307f8722c3961b01105c2deab29e198a13b7a1c
so the resource properties_data encryption is tested.

Change-Id: I7c720916511474b4f471a03235dddebf62dba085

openstack/heat,noironetworks/heat,steveb/heat,cwolferh/heat-scratch,cwolferh/heat-scratch,noironetworks/heat,openstack/heat,steveb/heat