Bug 15714: Add zebra_loglevels to koha-conf.xml

Bug 15714: Add zebra_loglevels to koha-conf.xml

This patch adds a commented zebra_loglevels line to the config file.
Behavior does not change, but an admin can easily edit the variable.

Test plan:
Nothing really changed. But if you are not so sure about that, apply the
change to /etc/koha/koha-conf-site.xml.in and run koha-create. Check
that the new koha-conf contains the line and is not messed up.

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Brendan Gallagher brendan@bywatersolutions.com