Bug 11715: require authentication for the cataloging Z39.50 search

Bug 11715: require authentication for the cataloging Z39.50 search

To test:
1/ go to /cgi-bin/koha/cataloguing/z3950_search.pl when you are not
logged in, notice no log in is enforced
2/ Apply patch
3/ go to /cgi-bin/koha/cataloguing/z3950_search.pl notice you now need
to login

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>