Use the AutoGrow plugin by default

Right now, when editing content in a wiki page in WYSIWYG mode, users are faced with 2 options:

• Edit their content in the textarea, which quickly triggers the appearance of 2 scrollbars (one for the textarea and one for the page itself), which can make the edition experience quite tedious when trying to move on the page

• Switch to full-screen edition mode, which hides a lot of the UI but removes the ability to edit the title (among other things)

In order to prevent both type of issues, I suggest we use the AutoGrow CKEditor plugin and activate it by default:

• Online demo: http://ckeditor.com/demo#auto-grow
• Plugin description: http://ckeditor.com/addon/autogrow

This would make the overall editing experience much more pleasant for users.