Message 167807 - Python tracker

That makes sense.  I've added a brief explanation noting that the user should be in the "Docs" directory to run the command.  When trying to update the dev guide, I noticed that this same "tools" directory does not exist in the repo, so I also added instructions for using the command as mentioned above.  For concision's sake, would it be good to remove the reference to the "tools/sphinx-build.py" file altogether?