Terminate NS NBI support

• Precondition: NS instance is INSTANTIATED state
• SOL007 NS packages are stored in ETSI Catalog Manager.
• the Cli-based SO NFVO Client is ready to send the SOL005-compliant Terminate NS request
• The SO-NFVO (so-etsi-nfvo) pod is ready

• Supports the SOL005-compliant Terminate NS API
  • Supports Terminate NS request API: POST /api/nslcm/v1/ns_instances/{nsInstanceId}/terminate (TerminateNsRequest)
  • Supports responses 202 Accepted with an empty payload body
    • Returns a dummy 202 until the backend business logic is ready 
    • Use a Location HTTP header that points to the new individual NS Lifecycle Operation Occurrence resource; i.e. the URI of that resource (.../ns_lcm_op_occs/{nsLcmOpOccId}
  • Supports the Sends nsLcmOperationOccurrenceNotifiation with nsLcmOpOccId, notificationStatus (start, result) until the result status becomes COMPLETED 
  • Optionally, Terminate NS operations uses the GET individual NS LCM operation occurrence request and response
• Error handling: if the operation is failed, error information is provided in the notification message

Note: secure communication is handled by a separate user story, SO-3165.