Attempt at static hosting

[ccoenen]

Looking over the express server code for #15, I realize that the express server is not actually needed any longer. As far as I can tell, this is now a fully static page that runs from the json files in /data, right? We don't actually have the database that sqlite would even work on in this repository.

If you want, I could try to create a github action for this project so that this could be hosted on Github Pages going forward. This has been suggested in #2, but at the time Heroku still worked just fine.