Implements notification listener and dispatcher
This patch allows to quickly create a listener to receive
notification messages.
Example of the api:
class Endpoint(object):
def warn(self, ctxt, publisher_id, event_type, payload):
do_something(payload)
target = messaging.Target(topic='notifications', exchange='cinder')
listener = notify.get_notification_listener(transport, [target],
[Endpoint()],
executor,
serializer)
Implements blueprint notification-subscriber-server
Change-Id: I434bc487c382a2048670df726d9bebd640150bb9
9f58e2c3fe