Merge topic 'policy-version-var' into release-4.0 1a35351125 Add CMAKE_POLICY_VERSION_MINIMUM to help configure outdated projects d723198539 Help: De-duplicate policy version documentation e5d29e9e00 Help: Drop cmake_minimum_required pre-2.4 behavior Acked-by: Kitware Robot <kwrobot@kitware.com> Acked-by: buildbot <buildbot@kitware.com> Merge-request: !10343