like LibreOffice java extensions, and nlpsolver and librelogo, do, removes the
magic number problem

Change-Id: I561249ccebe41c787cd8cdaa80e1d035f27052cc
Reviewed-on: https://gerrit.libreoffice.org/37986Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>