title: stop all actors in a system without shutting down the system itself?
body: <p>In Akka 2.0, is there a nice way to shut down all actors under the path /user?  For example, let's say that I do the following:</p>
  
  <pre><code>val system = ActorSystem.create("mySystem")
  
  system.actorOf(Props(new MyActor1), "actor1")
  system.actorOf(Props(new MyActor2), "actor2")
  </code></pre>
  
  <p>Some time later, I decide I want to stop all of the actors in the system.  If I understand things correctly, actor1 and actor2 will be children of the path /user, but I don't see a method that gives me an iterable of the children of an ActorRef.  Is there another way?</p>