[development] AHAH widgets

[Karoly Negyesi]

Hi,

Until now, adding AHAH to something defined in hook_elements was not
possible which was really, really sad as it made AHAH reusable
elements impossible. This is now fixed, Dmitri fixed AHAH and I
refactored/added some small FAPI parts. I hope that an example will be
committed tomorrow, I need to finish first, but it's coming along very
nicely. The example wll be an iTunes-styles drilldown selector for
menu/book in http://drupal.org/node/191360 .

Regards,

NK