Bug 18771: CGI.pm: Subroutine multi_param redefined

Bug 18771: CGI.pm: Subroutine multi_param redefined

The commands in the test plan are examples, and may need varying
depending on your installation. This was created as a result
of attempting to clean the installation process up. However,
I believe the redefine might exist normally too. I just didn't
check. This is tested on a Debian 8 box sudo apt-get update'd
fully.

TEST PLAN
---------
empty error log
$ echo > ~/koha-dev/var/log/koha-error_log

drop and recreate and empty db
> drop database koha_library;
> create database koha_library;
> quit

run the web installer, but DO NOT LOG IN!
*opening chrome to Staff Client URL*

check the error log
$ less ~/koha-dev/var/log/koha-error_log
...
[Fri Jun 09 13:08:52.793627 2017] [cgi:error] [pid 5802] [client 192.168.71.101:58169] AH01215: [Fri Jun  9 13:08:52 2017] CGI.pm: Subroutine multi_param redefined at /usr/share/perl5/CGI.pm line 419.
...

apply patch

empty error log
$ echo > ~/koha-dev/var/log/koha-error_log

refresh the installation login page

recheck the error log
$ less ~/koha-dev/var/log/koha-error_log

notice no reference to "Subroutine multi_param redefined"

run koha qa test tools

Notice that it is just a require CGI; and comment added.

Signed-off-by: Lee Jamison <ldjamison@marywood.edu>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>