only works on the way in.

add pass through to {$element['#type']}_widget_{$callback} to filefield_widget_{$callback}'s

imagefield now completely extends filefield... and filefield can use the imagefield widgets...
dirty promiscuous widgets...

fix default value assignment in filefield_widget.

remove some debug code...
add field_settings callback implementations.

allows modules to simply call filefield_widget_settings($op, $wiget)
and implement {$widget_type}_widget_settings_{$op} callbacks.
filefield_widget_settings will try to dynamically include {$module}_widget.inc
so you can put the settings outside your module as desired.

But not only that: The larger change in this commit is that all
restrictions have been split out into a validator/restriction hook,
so external restrictions can now also provide their requirement messages
for the file upload element.

Getting rid of nearly all filefield specific upload requirement exceptions.

add data column to file fields for widgets to store serialized data per item. (display settings, transform settings, etc).

add field_file_references($file, $field) to load references by field.
rename $item['filefield_delete'] to more descriptive $item['field_name'].

Extensible via hook_filefield_filesize_restrictions(), used for
displaying the upload form as well as for validating the actual uploads.
And of course, this comes with the new per-file and per-node file size
restriction "examples".

Note that the 5.x revision bug (#263162) does *not* appear anymore. Whoo!

(which happened on my local harddisk, so you didn't notice the revert at all)

filefield.formatter.inc and filefield.theme.inc work completely
with declarational 'file' properties in the various hooks,
whereas filefield.widget.inc still needs to be included manually.