ROOT macOS Fix, 1.0 branch (2017.08.01.)
Turned off the build of Davix (as part of ROOT) on all platforms other than SLC6. Since at least on macOS it doesn't build out of the box. So it seemed safer to turn it off everywhere where we didn't test/need it.
This is to fix the issue mentioned, amongst other places, in ATLASG-1270.