Bug 19103 - Stored XSS in itemtypes.pl

Bug 19103 - Stored XSS in itemtypes.pl

To Test
1. Hit the page /cgi-bin/koha/admin/itemtypes.pl
2. Add a text in the field Description, Checkin message that contains js
2. Save the page.
3. Notice js is execute
4. Apply patch and reload, the js is escaped

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
(cherry picked from commit 18b5d4f1ababf560ff02a258de389f8c34cff9e4)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>