Fixed issue with document.formvalidator not being defined

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=32637

This fixes the issue of the document.formvalidator being called too early causing all other javascripts to fail.

The Joomla.submitbutton javascript should not be placed in the head, but in the body of the html (like all other edit views in core do).