Add basic wysiwyg(ckeditor) to article and page editors

The editor provides the ability to:
* Add a H1, H2, H3 etc.
* Bold
* Italic
* Underline
* Bullet point
* Number lists
* Indent

Remove spaces around the param and put the opening brace on the same line, per [the styleguide](https://github.com/moneyadviceservice/javascript#functions)