title: falcor: Subscribe to model changes?
body: <p>Is it possible to subscribe to model changes, i.e. suppose I want to <code>get('todos[0]["completed"]').subscribe(//render function)</code> and after <code>setValue('todos[0]["completed"]', true)</code> model emits new data and render function is invoked with this new data? </p>
  
  <p>I tried the exact same approach as described, but for some reason render function is not invoked after setValue</p>