#816090 by Dave Reid: Rename all HTML5 elements to [type]field to avoid further namespace conflicts.

#875280 by Dave Reid: Remove imagebutton field since Drupal 6 core added the image_button FAPI element type.

Initial commit of elements module - This module intends to become a repository for advanced form elements, other developers can use. For now, it contains a tableselect element type that can be used to easily create tables as seen on admin/user/user. It also contains an imagebutton ripped from views, but this does not work satisfactorily. This module was commissioned by the NCRV (http://www.ncrv.nl)