Basics to get it working again (and running in Codespaces)

[mountainash]

I guess it's been a while since this project ran....

I've updated it to "minimally" work on Python 3 (and run in a Docker Container using GitHub CodeSpace - easy).

I've fixed up the main.html to find a CDN version of jQuery it needed and some mods to the Python to get it running.

I've updated the docs for users to get it running as I'd imagine that there's a bit more traffic to this project now that the 2 Google App Engine services linked from the highly ranked blog post are now failing (indecently, it would be good if the code from the GAE examples was in this project too?)