Ceilometer/MeteringNotifications

alarm.deletion:

 * C[r]UD operations on Alarm definitions
 * event_id: Event UUID (string)
 * alarm_id: Alarm UUID (string)
 * type: alarm type. (string)
 * detail: details of change. (dict)
 * user_id: user_id (int)
 * project_id: project_id (int)
 * on_behalf_of: user id of acted on user (int)
 * timestamp: time of change (string)