handle tar.xz tarballs
handle tar.xz tarballs

Change-Id: I8e36ad989ec54117f85105c24bc1c1442e0a493b
Reviewed-on: https://gerrit.libreoffice.org/15454
Reviewed-by: Andras Timar <a6d402970b646b92d0c38c744d46432a07992d80@collabora.com>
Tested-by: Andras Timar <a6d402970b646b92d0c38c744d46432a07992d80@collabora.com>

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core