title: How do I pass reference to Navigator into renderScene?
body: <p>I've been experimenting with React Native and I'm having trouble passing a reference to navigator into the scene I'm rendering. Without navigator, NewsList items can't trigger a scene change.</p>
  
  <pre><code>render: function() {
      return (
          &lt;Navigator
              initialRoute={ { name: 'NewsList', index: 0 } }
              renderScene={ ( route, navigator ) =&gt; NewsList }
          /&gt;                                                      
      );                                                          
  },
  </code></pre>
  
  <p>Similarly, in the render scene function I need to pass navigator to the row rendering function.</p>
  
  <pre><code>&lt;UIExplorerPage noSpacer={true} noScroll={true}&gt;
      &lt;ListView
          dataSource={this.state.dataSource}
          renderRow={this._renderRow}
          onEndReached={this.onEndReached}
      /&gt;
  &lt;/UIExplorerPage&gt;
  </code></pre>
  
  <p>What is the idiomatic way to pass references like this around?</p>