title: canActivate issue with durandal 2.0.1
body: <p>I downloaded Durandal 2.0.1 StarterKit and I am using it for a web project. I worked with it for a while now.</p>
  
  <p>In one of my viewmodels I am using the routing with id in the url: <code>route: 'test/:id'</code>. Since I want to protect against random id inputs from the user, I am using the <code>canAvtivate</code> function, in which I perform some checks.</p>
  
  <p>When I'm trying to access the route from another route the <code>canActivate</code> function is evaluated before activating, but when i just change the id value in the url the function is not called. It happens the same if I say <code>router.navigate("#/test/44");</code> from within that view.</p>
  
  <p>Is this desired behavior?</p>