Bug 6874: kohastructure.sql, jquery.js, refocus, and more

Bug 6874: kohastructure.sql, jquery.js, refocus, and more

Two problems were discovered while doing a fresh install
of Koha. These problems in the kohastructure.sql file are
addressed with this patch.

Clicking the plug-in icon should cause the popup window
to refocus.  This adds the refocus code to the upload.pl file.

The path to the jquery.js script was wrong in the
upload_delete_file.tt file. Changed [% themelang %] to
[% interface %].

If a user clones 856$u after uploading a file, deletes the file,
and then clicks the plugin icon on the first 856$u, this will go
immediately to the upload screen with an informative error
message.

After some validation was added, it was extended to include
other cases. This serves to patch 6874 to a state where sign
off should be possible.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>