DESCRIPTION
An input field that renders using "<input type="file" />". The argument value that the action receives from this field via ``argument_value'' in Jifty::Action will be a filehandle, which can be read in the usual ways.render_widget
Renders the file upload widget.render_value
The 'value', rendered, is empty so that BLOBs and the like don't get streamed to the browser.classes
Add 'upload' to the rest of the classes