title: Ember reload array controller when item in array changes
body: <p>I have an ArrayController in which I am showing 2 groups of objects filtered by 'group.'  When I edit a person, I can change their group using an Ember select and I can see the group changed in the list, but  the question is how do I notify the parent ArrayController that it needs to reapply the filters and re-render the {{#each}} blocks?</p>
  
  <p>Here's a JSBin that shows the problem.  <a href="http://jsbin.com/ISIKAjOZ/5/edit" rel="nofollow">http://jsbin.com/ISIKAjOZ/5/edit</a></p>
  
  <p>To see this in the JSBin, click on one of the people and change their group using the drop down.  You'll see their group number update, but they need to move from one list to the other...</p>