refresh openstack credentials when creating a slice's network and router
diff --git a/plstackapi/core/models/slice.py b/plstackapi/core/models/slice.py
index dc2fc63..5a5f165 100644
--- a/plstackapi/core/models/slice.py
+++ b/plstackapi/core/models/slice.py
@@ -34,6 +34,11 @@
             # give caller an admin role at the tenant they've created
             self.driver.add_user_role(self.caller.user_id, tenant.id, 'admin')
 
+            # refresh credentials using this tenant
+            self.driver.shell.connect(username=self.driver.shell.keystone.username,
+                                      password=self.driver.shell.keystone.password, 
+                                      tenant=tenant.name) 
+
             # create network
             network = self.driver.create_network(self.name)
             self.network_id = network['id']