title: Knockout afterRender, but just once
body: <p>I have a simple observableArray which contains a lot of user-models.
  In the markup, there is a template with a foreach loop which loops the users and outputs them in a simple table. I additionally style the table with a custom scrollbar and some other javascript. So now I have to know when the foreach loop is finished and all the models are added to the DOM. </p>
  
  <p>The problem with the afterRender callback is that it gets called every time something is added, but I need kind of a callback which fires only once. </p>