CKEditor 4.4.0 and external plugins loading

Hi,

I updated CKEditor to 4.4.0 and added support for widgets and external plugins loading, because, I need to allow users to insert HTML like this

```html
<div class="headline">
  <h2>Title</h2>
</div>
```

into area, so that the user can modify only the "Title" string. CKEditor 4.4 has nice support for [Widgets](http://docs.ckeditor.com/#!/guide/widget_sdk_intro)

Developers can now extend CKEditor throught their own plugins.

Here is the example of the plugin which I have placed to the `/public/editor/plugins/headline/plugin.js` in my project:

```js
( function() {
  CKEDITOR.plugins.add('headline', {
    requires: 'widget',

    icons: 'headline',

    init: function(editor) {
      editor.widgets.add('headline', {
        button: 'Create headline',

        template: '<div class="headline">\n    <h2 class="headline-title">Title</h2>\n</div>',

        editables: {
          title: {
            selector: '.headline-title',
            allowedContent: 'em strong'
          }
        },

        allowedContent: 'div(!headline); h2(!headline-title)',

        requiredContent: 'div(headline)',

        upcast: function(element) {
          return element.name == 'div' && element.hasClass('headline');
        }
      });
    }
  })
}() );
```

And then in the HTML:

```
{{ aposArea(global, 'footerAbout', {
   textOnly: true,
   controls: [ 'style', 'italic', 'bold', 'createLink', 'unlink', 'Headline' ],
   plugins: [ { name: 'headline', path: '/editor/plugins/headline/' } ]
}) }}
```