Bug 14078: (followup) converting from ISO5426 is not complete

Bug 14078: (followup) converting from ISO5426 is not complete

Conversion of MARC from ISO5426 is defined in C4::Charset::char_decode5426().
Each character or combined characters conversion is defined in a map.

This patch adds missing conversions.

See http://www.gymel.com/charsets/MAB2.html

Signed-off-by: Frederic Demians <f.demians@tamil.fr>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 636050f9be374fc15acad8b047c1ae227d38b225)
Signed-off-by: Frédéric Demians <f.demians@tamil.fr>