Defines and implements create|end|error notifications for
all state-changing Trove API calls. Adds a notification to
the TroveContext to transfer the notification to the guest
and conductor so that errors on asynchronous commands can
be forwarded to the Conductor to be transferred to the
control plane bus.
Also did some cleanup on the existing notifications to bring
them all under a common framework in trove/common/notifications.py.
The trove.instance.exists notification was not integrated into
the new framework due to its close-coupling with the Nova
notification code.
Reworked the cluster action mechanism to move routing
functionality from the strategy to the Cluster base
class. This was done to support tying notifications
to cluster specific actions.
Implements Blueprint: ceilometer-integration
Change-Id: I9c57d24f80d8d3116fc0cc8948094087a0495135
Morgan Jones
5c29f40d5f