axis labels and vertical axis lines. If the same
value labels follow each other, because of
the number format, only display them once.

Change-Id: I3c5577a0e86c475cb2fafb62d63f991cef7229d8
Reviewed-on: https://gerrit.libreoffice.org/73200
Tested-by: Jenkins
Reviewed-by: László Németh <nemeth@numbertext.org>