title: How to destroy template instance?
body: <p>I have a game template rendered by iron router (when you go into the game from default page).
  When the game finished, I want the player to be routed to default page and the current game template instance to be removed.</p>
  
  <p>For this purpose I use a hook on removed event for game collection. Which allows other players to be automatically redirected to default page when game ends:</p>
  
  <pre><code>Tempalte.game.rendered = function () {
    var self = this;
    var gameId;
    //some code here
    var game = Games.find({name: Session.get('gameName')});    
    game.observeChanges({
          added: function(id, fields) {
              gameId = id;
          },
          removed: function(id) {
              if (gameId === id) { Router.go('/');
                 alert("Game finished");}
          }
      });
  }
  </code></pre>
  
  <p>When I finish the game and create new one with the same name. The alert called twice.
  One more finish/create => Three alerts.
  It looks like the game template instance still remains somewhere in the background and monitors changes in Games collection.</p>
  
  <p>So the question is how to properly remove the template instance when going to default page?
  Tried Blaze.remove(self) not working because the game template wasn't rendered with Blaze.render().
  In the router I don't know how to get the handle for the template instance.</p>