add support for calling new VTN API

Change-Id: I706c6fbb7182ee53f0df6d6b74fd6305cd23b492
diff --git a/xos/models.py b/xos/models.py
index c805f24..9833628 100644
--- a/xos/models.py
+++ b/xos/models.py
@@ -39,6 +39,7 @@
                           ("xosEndpoint", "http://xos/"),
                           ("xosUser", "padmin@vicci.org"),
                           ("xosPassword", "letmein"),
+                          ("vtnAPIVersion", 1),
 
                          )