* library/download.ith (completed_steps): New variable.

    * library/download.ith (completed_steps): New variable.
        * library/download.itb (Download::constructor): Remove
        "-fraction" option from iwidgets feedback widget. It's not a valid
        option!
        (update_download): Compute the step number and use that to
        update the feedback widget.
        (done): Use completed_steps to figure out how many steps
        the dumb feedback meter needs to show full.