GetQuickHelpText() returns the value of the tooltip text.
So moving them into .ui file as tooltips.

Change-Id: If7f8f5a585f5a765b0c41374beec2843c0335e75
Reviewed-on: https://gerrit.libreoffice.org/26389Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>