title: Akka's ActorSystem Shutdown?
body: <p>please
  how to shutdown actorSystem after all childs' actors finished</p>
  
  <pre><code>system().shutdown //cut actors work
  </code></pre>
  
  <p>i try to use </p>
  
  <pre><code>system().shutdown
  </code></pre>
  
  <p>but this cut other actors work</p>
  
  <p>and schedule may finish before child actors finished </p>