GrabBag the settings which LO doesn't implement
(which is all of them) so that the document
round-trips without losing the config settings.

Change-Id: I00de6c483af68073634430dd74fd445e981573ab
Reviewed-on: https://gerrit.libreoffice.org/62241
Tested-by: Jenkins
Reviewed-by: Justin Luth <justin_luth@sil.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>