title: Replacing selected text in the textarea
body: <p>what is the best way to do this in jQuery? This should be a fairly common use case.</p>
  
  <ol>
  <li>User selects text in a textarea </li>
  <li>He clicks on a link </li>
  <li>The text in the link replaces the selected text in the textarea</li>
  </ol>
  
  <p>Any code will be much appreciated - I am having some issues with part 3. </p>