title: Correct use of React fragments with array of elements in React 16
body: <p><code>headTags</code> is an array of React elements without any keys defined. I am able to render without warnings using the following JSX.</p>
  
  <pre><code>return (
    &lt;head&gt;
      {React.Children.toArray(headTags)}
    &lt;/head&gt;
  );
  </code></pre>
  
  <p>Is there some possible way to do this with fragments in React 16? I get a warning that a <code>key</code> is required for each child element when using this:</p>
  
  <pre><code>return (
    &lt;head&gt;
      &lt;React.Fragment&gt;
        {headTags}
      &lt;/React.Fragment&gt;
    &lt;/head&gt;
  );
  </code></pre>