macos: next version support

macos: next version support

support things beyond 10.7

Reviewed-on: http://gerrit.openafs.org/7763
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Tested-by: Derrick Brashear <shadow@dementix.org>
Reviewed-by: Derrick Brashear <shadow@dementix.org>
(cherry picked from commit 73ff09513013ae3c6b29b1b7b0a6e76b4fd260f7)

Change-Id: I0bbef00747b01b387989398557fb82be93fe28f9
Reviewed-on: http://gerrit.openafs.org/8785
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Paul Smeddle <paul.smeddle@gmail.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>