This patch refactors the sample files of aggregate-add_host,
aggregate-delete, aggregate-create and aggregate-remove_host
notifications to use a common AggregatePayload sample data.
Change-Id: I50382f4d829693412bbfe47ffd08a24e69342715
The aggregate.add_host.start and aggregate.add_host.end notifications
has been transformed to the versioned notification framework.
Note that the legacy event_type was aggregate.addhost but the versioned
notification is named to aggregate.add_host to keep the naming consistent
with the other event_types.
Implements: bp versioned-notification-transformation-queens
Change-Id: I980d89f47b944116e5fc9cedd74c43bbd88fbeae