def started(topic, event)
      subscribers_for(topic).each{ |subscriber| subscriber.started(event) }
    end
def started(topic, event)
      subscribers_for(topic).each{ |subscriber| subscriber.started(event) }
    end
Publish a started event.

 @example Publish a started event.
   monitoring.started(COMMAND, event)

 @param [ String ] topic The event topic.
 @param [ Event ] event The event to publish.

 @since 2.1.0