Bug 21480: misc/translator/translate does not work with perl 5.26

Bug 21480: misc/translator/translate does not work with perl 5.26

Perl 5.26 (or earlier) introduced a security feature, where implicitly
including the program directory as a Perl library directory no longer
happens (perl -I. ).

This causes translate to fail because it cannot find the *.pm -files in
it's own directory.

This patch adds the familiar mantra
    use lib $FindBin::Bin;
to the relevant scripts.

To test:

1. Install Ubuntu18.04 or something else with Perl 5.26
2. Install Koha (we use the dev-install)
3. cd $KOHA_PATH/misc/translator/
4. perl translate create fi-FI
5. Observe problems with missing modules.

Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Cannot recreate the issue right now but the changes make sense.

Signed-off-by: Nick Clemens <nick@bywatersolutions.com>