Vendor continuity

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

vendor/github.com/stevvooe/continuity/devices_darwin.go

@@ -0,0 +1,15 @@
+package continuity
+
+// from /usr/include/sys/types.h
+
+func getmajor(dev int32) uint64 {
+	return (uint64(dev) >> 24) & 0xff
+}
+
+func getminor(dev int32) uint64 {
+	return uint64(dev) & 0xffffff
+}
+
+func makedev(major int, minor int) int {
+	return ((major << 24) | minor)
+}