add support to append value into policyScope while one policy could be used by several services

background:
OOF fetch policy by scope, the value of scope is service.
one policy could be used by several services. the value of policyScope is like below:
"policyScope": "vfw,vcpe,us,international,ip,vsn,vcpe_demo_withall_01,vcpe_with_all,vcpe_with_vbng"

in currently forward implementation, it just simple use create/push to forward policy:
boolean policyCreated = createPolicy(policyAdapter);
if (policyCreated)

once the policy is used by several services, the createpolicy will meet the problem, it will reports error as" same name policyname has existed".

manually: user could append a new service into the policyScope field by update the policy.
Automatically: forward needs update to deal with such case once one policy is used by several services.