Video/object track aggregation event

[bsriramprasad]

Here is the summary of changes included in PR

• Created a new section "Object Track Aggregation" event description in Analytics specification
• Created schema structures referred in the event description
• No additional changes in Metadata configuration, follows existing Event transport.
• Not defined as a property event
  • Primary use case to standardize only the 'final aggregation'
  • Initial/intermediate aggregations are made optional
  • use case NOT at all focused to get the state of every object in the scene at any time.
  • If we are sending only one (final aggregation) event per object, it is an overkill to fit into the property event paradigm.