title: CKEditor how to pick up what has been highlighted
body: <p>I am attempting to creat an extra plugin for ck editor.</p>
  
  <p>I have created a button on the toolbar and am at the stage to do something when this is clicked....</p>
  
  <pre><code>CKEDITOR.plugins.add('enlarge',
  {
      init: function (editor) {
          //Plugin logic goes here.
          editor.addCommand('insertenlarge',
              {
                  exec: function (editor) {
  
              }
          });
  
          editor.ui.addButton('enlarge',
              {
                  label: 'Insert enlarge',
                  command: 'insertenlarge',
                  icon: this.path + 'images/enlarge.png'
          });
      }
  });
  </code></pre>
  
  <p>What I dont know is how to get the highlighted element. Basically i want the user to click on an image in the editor and click enlarge and it opens the image up in a new pop up, i just want to be able to for now find out how to access the image element so i can place it in a pop up?</p>