In case of mirrored pages the gutter cannot be left or right but
inner or outer. To make the dialog easier to understand the modifier
checkbox for Left turning this into Right was changed to radio buttons.
Change-Id: I71b32d89f9a9054f5351e3c0d51ba348b66c1f0c
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/209072
Tested-by: Jenkins
Reviewed-by: Heiko Tietze <heiko.tietze@documentfoundation.org>
Heiko Tietze
c99cf5b32b