HPCC-10995 Add Serbian Cyrillic (SR)

Fixes HPCC-10995

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #5518 from GordonSmith/HPCC-10995

HPCC-10995 Add Serbian Cyrillic (SR)

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>