Master comment updated

manifests/setup/sharednetwork.pp

 # A static class to set up a shared network. Should appear on the
-# controller node. It sets up the public network, a private network,
-# two subnets (one for admin, one for test), and the routers that
-# connect the subnets to the public network.
+# controller node. It sets up the public network(s), private network(s),
+# subnets (for admin and for test), and (if enabled) the routers that
+# connect the subnets to the public network(s).
 #
 # After this class has run, you should have a functional network
 # avaiable for your test user to launch and connect machines to.