note about starting server

lms/djangoapps/acceptance_testing/README.md

@@ -2,6 +2,8 @@
 
 This fake django app is here to support acceptance testing using lettuce + selenium. Some documentation for our efforts are located in basecamp: https://basecamp.com/1892446/projects/841513-release/documents/1015202-staging-tests
 
+You need to start the server first
+
 Running all lettuce tests
 
 ```django-admin.py harvest --settings=lms.envs.acceptance_testing --pythonpath=. --no-server```