Transition to show only incomplete todos

http://guides.emberjs.com/v1.10.0/getting-started/show-only-incomplete-todos/

```
ember g route todos/active
rm app/templates/todos/active.hbs
```

app/router.js

@@ -8,7 +8,9 @@ var Router = Ember.Router.extend({
 Router.map(function() {
   this.resource('todos', {
     path: '/'
-  }, function() {});
+  }, function() {
+    this.route('active');
+  });
 });
 
 export default Router;

app/routes/todos/active.js

@@ -0,0 +1,12 @@
+import Ember from 'ember';
+
+export default Ember.Route.extend({
+  model: function(){
+    return this.store.filter('todo', function(todo) {
+      return !todo.get('isCompleted');
+    });
+  },
+  renderTemplate: function(controller) {
+    this.render('todos/index', {controller: controller});
+  }
+});

app/templates/todos.hbs

@@ -24,7 +24,7 @@
         <a href="all" class="selected">All</a>
       </li>
       <li>
-        <a href="active">Active</a>
+        {{#link-to "todos.active" activeClass="selected"}}Active{{/link-to}}
       </li>
       <li>
         <a href="completed">Completed</a>

tests/unit/routes/todos/active-test.js

@@ -0,0 +1,14 @@
+import {
+  moduleFor,
+  test
+} from 'ember-qunit';
+
+moduleFor('route:todos/active', {
+  // Specify the other units that are required for this test.
+  // needs: ['controller:foo']
+});
+
+test('it exists', function(assert) {
+  var route = this.subject();
+  assert.ok(route);
+});