title: EventKeys in NavDropdown in React-Bootstrap
body: <p>I have a problem with the eventKey thing in NavDropdowns.</p>
  
  <pre class="lang-jsx prettyprint-override"><code>var Navigation = React.createClass({
  
    handleSelect: function(eventKey){
      console.log(eventKey);
    },
  
    render: function() {
      return (
        &lt;Navbar brand='Navbar' toggleNavKey={0}&gt;
          &lt;CollapsibleNav eventKey={0} onSelect={this.handleSelect}&gt;
  
            &lt;Nav navbar&gt;
              &lt;NavItem eventKey={1}&gt;Home&lt;/NavItem&gt;
            &lt;/Nav&gt; 
  
  
            &lt;Nav navbar right hide&gt;
              &lt;NavItem eventKey={2}&gt;Login&lt;/NavItem&gt;
  
              &lt;NavDropdown eventKey={3} title='NavDropdown' id='basic-nav-dropdown'&gt;
                &lt;MenuItem eventKey={4}&gt;Action 1&lt;/MenuItem&gt;
                &lt;MenuItem eventKey={5}&gt;Action 2&lt;/MenuItem&gt;
              &lt;/NavDropdown&gt;
            &lt;/Nav&gt;
  
          &lt;/CollapsibleNav&gt;
        &lt;/Navbar&gt;
  
      )
    }
  });
  </code></pre>
  
  <p>I want to be able in my selectHandler to tell what Nav element was clicked.
  This works great for all elements except the NavDropdown:</p>
  
  <p>Clicking the Dropdown does not trigger the selectHandler, which is fine.
  But when I click one of the MenuItem, instead of giving me the eventKey, it gives me an event object.</p>
  
  <p>How can I modify the NavDropdown so that it gives me the eventKey?</p>
  
  <hr>
  
  <p>Edit: My versions are:</p>
  
  <pre><code>"react": "^0.14.0-beta3",
  "react-bootstrap": "^0.25.100-react-pre.0",
  </code></pre>