For fine-grained access control based on user and VNF information
for API resources, this patch does the following things:
1.Add three comparison attributes of area, vendor, and tenant
for the enhanced Tacker policy.
2.Convert special roles to API attributes in context.
3.Modify the API process to support Tacker policy authorize.
4.Add the Tacker policy filter to the list API processes.
Implements: blueprint enhance-api-policy
Change-Id: I5b4c39387860133a3bcf4544f18a6353c80773f6
05fe9fa42c