During import, as well during export, "0.--" must be considered
as 0 min decimal places

Change-Id: I33d06dd95c0678660bc0bb222972f82ef54f2c6e
Reviewed-on: https://gerrit.libreoffice.org/19647Reviewed-by: Eike Rathke <erack@redhat.com>
Tested-by: Eike Rathke <erack@redhat.com>
(cherry picked from commit 3f970cf2)
Reviewed-on: https://gerrit.libreoffice.org/19781
(cherry picked from commit 18be99af)