look for methods returning only 1 and/or 0, which (most of the time)
should be returning bool.

Off by default, because some of this is a matter of taste

Change-Id: Ib17782e629888255196e89d4a178618a9612a0de
Reviewed-on: https://gerrit.libreoffice.org/54379Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>