Bug 13612 - Remove old YUI javacript libraries from opac-tmpl

Bug 13612 - Remove old YUI javacript libraries from opac-tmpl

YUI files were left behind in opac-tmpl/lib/yui after the removal of the
prog theme. These files are unused and can be safely removed.

To test, apply the patch and search for references to any of the YUI
files. You should find none in the OPAC templates.

No references found.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>