Networking URL construction no longer adds /v2.0

Because it's already handled by the ResourceBase that's set up when you
acquire a client.
diff --git a/openstack/networking/v2/extensions/delegate_test.go b/openstack/networking/v2/extensions/delegate_test.go
index 7dff12b..8de8906 100755
--- a/openstack/networking/v2/extensions/delegate_test.go
+++ b/openstack/networking/v2/extensions/delegate_test.go
@@ -15,7 +15,7 @@
 	th.SetupHTTP()
 	defer th.TeardownHTTP()
 
-	th.Mux.HandleFunc("/v2.0/extensions", func(w http.ResponseWriter, r *http.Request) {
+	th.Mux.HandleFunc("/extensions", func(w http.ResponseWriter, r *http.Request) {
 		th.TestMethod(t, r, "GET")
 		th.TestHeader(t, r, "X-Auth-Token", fake.TokenID)
 
@@ -73,7 +73,7 @@
 	th.SetupHTTP()
 	defer th.TeardownHTTP()
 
-	th.Mux.HandleFunc("/v2.0/extensions/agent", func(w http.ResponseWriter, r *http.Request) {
+	th.Mux.HandleFunc("/extensions/agent", func(w http.ResponseWriter, r *http.Request) {
 		th.TestMethod(t, r, "GET")
 		th.TestHeader(t, r, "X-Auth-Token", fake.TokenID)