Bug 19050 - XSS Flaws in Quick spine label creator

Bug 19050 - XSS Flaws in Quick spine label creator

1. Hit /cgi-bin/koha/labels/spinelabel-home.pl
2. Enter <IFRAME SRC="javascript:alert('XSS');"></IFRAME> barcode text box.
3. Notice the iframe is executed
4. Apply patch
5. Reload page, and enter iframe again on barcode text box.
6. Notice it is no longer executed

Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>