Add swift-ring-builder multi region support

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

README.md

@@ -60,6 +60,7 @@ class { 'swift::storage::all':
 }
 
 @@ring_object_device { "${ipaddress_eth0}:6000/1":
+  region => 1, # optional, defaults to 1
   zone   => 1,
   weight => 1,
 }
@@ -73,14 +74,17 @@ class { 'swift::storage::all':
 }
 
 @@ring_object_device { "${ipaddress_eth0}:6000/2":
+  region => 2,
   zone   => 1,
   weight => 1,
 }
 @@ring_container_device { "${ipaddress_eth0}:6001/2":
+  region => 2,
   zone   => 1,
   weight => 1,
 }
 @@ring_account_device { "${ipaddress_eth0}:6002/2":
+  region => 2,
   zone   => 1,
   weight => 1,
 }