Add ONAP-XACML StdEngine tests

Re-worked some JUnits to ensure they really are testing correctly.

added coverage to the factory and std engine for easy exception
conditions.

Issue-ID: POLICY-2242
Change-Id: Iff6a390bff871fea2836336b77567f4a35720dfd
Signed-off-by: Pamela Dragosh <pdragosh@research.att.com>
4 files changed