Related: rhbz#1032774 slide restarter should disable auto-exit

The scenario is a pps that exits the app when the presentation
is complete. But using "switch screens" in the presenter
console will stop and restart the presentation. So protect
that "stop" against existing by disabling the autoexit
and restoring it afterwards

(cherry picked from commit b7197cfe5d207b171412760c6d72353f31947e93)

Conflicts:
	sd/source/ui/slideshow/slideshow.cxx

Change-Id: Id986ad7e3cfafb8068540fb90d05443f329b554c
Reviewed-on: https://gerrit.libreoffice.org/9166
Tested-by: Andrzej Hunt <andrzej.hunt@collabora.com>
Reviewed-by: Andrzej Hunt <andrzej.hunt@collabora.com>