title: React CDN based page not working with Babel 6.1.19
body: <p>The following React code works when the Babel-Core CDN is changed to version 5.8.24 but not when the version is 6.1.19 as included. I am heavily confused as to why this would matter? Shouldn't things be forward-compatible? Or am I just missing something really obvious here?</p>
  
  <p>Thanks in advance.</p>
  
  <pre><code>&lt;html&gt;
  &lt;head&gt;
      &lt;script src="https://unpkg.com/react@15/dist/react.min.js"&gt;
  &lt;/script&gt;
      &lt;script src="https://unpkg.com/react-dom@15/dist/react-dom.min.js"&gt;
  &lt;/script&gt;
      &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/babel-
  core/6.1.19/browser.min.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div id="app"&gt;&lt;/div&gt;
      &lt;script type="text/babel"&gt;
          const HelloMessage = React.createClass({
              render: function() {
                  return &lt;div&gt;Hello {this.props.name}&lt;/div&gt;;
              }
          });
  
          ReactDOM.render(&lt;HelloMessage name="John" /&gt;, 
  document.getElementById('app'));
      &lt;/script&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>