README.rst of tempest stress is misleading

Change-Id: I6f533766c4c19023eff2ffa3fc62f6e1f82a4215
Closes-Bug: #1229299
diff --git a/tempest/stress/README.rst b/tempest/stress/README.rst
index 7c180f6..ae86f6e 100644
--- a/tempest/stress/README.rst
+++ b/tempest/stress/README.rst
@@ -31,7 +31,7 @@
 
 To test installation, do the following (from the tempest/stress directory):
 
-	./run_stress.py etc/server-create-destroy-test.json -d 30
+	./run_stress.py -t etc/server-create-destroy-test.json -d 30
 
 This sample test tries to create a few VMs and kill a few VMs.