Event Schema V2 to support delete operation

To send notification for 'DELETE' operation from cps-core, the existing event schema needs to be changed and the changes are and documented https://wiki.onap.org/x/54IEBw 

Test cases should also validate that

• the event v2 is backwards compatible. ( v2 Java class should be able to process v1 event)
• v2 is forward compatible if any new options field is added. ( v2 Java class can also process events with unknown optional fields in it.

This story impacts only changes the schema and test the generated Java code. The changes in the notification service and cps-temporal will be handled in separate stories

1. Update src/main/resources/schemas/cps-data-updated-event-schema.json as per v2 schema in https://wiki.onap.org/x/54IEBw 
2. Add/change groovy test for 
   1. Version 2 event
   2. Version 2 event with additional field
   3. Version 1 event (backward compatibility)

A/C

• Demo (depending on other user stories)
• Groovy tests covering both current and 'future' compatibility