Bug 28519: Add lib to koha-shell

Bug 28519: Add lib to koha-shell

Test plan:
% koha-shell kohadev -c 'echo $PERL5LIB'
=> /kohadevbox/koha:/kohadevbox/koha/lib

% koha-shell kohadev
echo $PERL5LIB
=> /kohadevbox/koha:/kohadevbox/koha/lib:/kohadevbox/qa-test-tools

Note that this is not consistent but at least we have lib now in both
situations

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>