Bug 14321: Final cleanup, removing obsolete files

Bug 14321: Final cleanup, removing obsolete files

The new Upload.pm, unit test and file-upload.js obsolete a number of
files, including an older jQuery plugin.
The test files progressbar.pl and progressbarsubmit.pl are outdated and
do not serve any purpose in this form. (Actually, we could argue if they
should be here or just be part of a debugging phase.)

Test plan:
[1] Git grep on file-progress, file-upload.inc, UploadedFile,
    ajaxfileupload, ajaxFileUpload
    UploadedFile: Only a reference to DBIx file is found
    ajaxfileupload: Only release notes
[2] Upload a file with tools/upload and stage-marc-import.

Signed-off-by: Mirko Tietgen <mirko@abunchofthings.net>
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>