Better docs

circle.yml

@@ -71,9 +71,12 @@ dependencies:
     #
     # This line is useful to debug builds that fail because of excessive memory
     # usage, such as https://circleci.com/gh/andresriancho/w3af/2819#tests/containers/0
-    # Those builds are hard to debug since the build VM is killed and no
-    # artifact is collected, so we need to know which tests were running
-    # using the stdout output from the test runner + this script.
+    #
+    # Those builds are hard to debug since the build VM is killed and the only
+    # collected artifact is memory-usage.txt. In that file you should find the
+    # test ID which was running when circleci killed the build. Using that ID
+    # and the output of this tool, you'll be able to pinpoint which test was
+    # using a lot of memory.
     - python w3af/core/controllers/ci/nosetests_wrapper/show-test-ids.py
 
     # Might need more waiting for the docker-compose up command to finish