bb3007615f
Since Swift 1.8.0, there is the region layer of topology above zones. swift-ring-builder supports this natively and this commit allows a user to specify a region when creating devices. We maintain backwards compatibility by defaulting to region '1'. The coverage of the ring builder spec tests were also improved as part of this commit. Change-Id: I67cbe6b87c84778f71df59cf00f2c5175342bc1b