[POLICY-11] New REST APIs to obtain facts info

[POLICY-11] New REST APIs to obtain facts info

The following REST APIs have been added, shown by example:

GET policy/pdp/engine/controllers/<controller-name>/drools :
  drools information for controller named <controller-name>

For brevity in URL description, assume:
DROOLS-REL-PATH=policy/pdp/engine/controllers/<controller-name>/drools

GET ${DROOLS-REL-PATH}/<session-name>[?count=true]
  fact classes and count for <session-name> in controller <name>

GET ${DROOLS-REL-PATH}/<session-name>/<classname>
  all fact objects of class <classname> for session <session-name>

GET ${DROOLS-REL-PATH}/<session-name>/<query-name>/<query-id>
  all fact objects returned by drools query named <query-name>
  for the identifier <query-id>
  (need corresponding query definition in drl is necessary)

Change-Id: I2f62931f54a65eec4ef80472ad1af05f30ed83ba
Signed-off-by: Jorge Hernandez <jh1730@att.com>