Docker setup & instructions

[alexedelsburg]

Added a Dockerfile to build an image and instructions to run it

Tested by

1. Running on my machine (macOS with Colima instead of Docker)
2. Converting a save file
3. Comparing the md5sum of the output from the docker-ized version and the version at https://savefileconverter.com

[euan-forrester]

Thanks for this!

I'm going to let it sit and think about it for a while. I've been deliberately vague and obtuse with the instructions on how to run this locally because hardly anyone actually needs to (although some people want to despite not needing to). I don't want to create a support burden for myself. The vast majority of users of this site are nontechnical and this method of running the site may create more questions than answers ("what is docker?", etc)

[euan-forrester]

I've spent some time thinking about this and I've decided to decline this PR.

This just isn't a use case that I want to support. I made the system be online so that it's easy to update and the current version is always live.

The users of this site are disproportionately "collector oriented" and disproportionately nontechnical. Meaning that many users want to possess things (like games), which carries over to a desire to "possess" this website. However, the vast majority of users of this site do not have the technical ability to run even this simple docker script.

A very very small number of users have a solid reason for wanting to have an offline version of the site, such as a military deployment overseas, and I'm happy to support them on a case-by-case basis. But many more simply "want" it, and I don't want this added support burden. The burden both of helping them use docker, and of dealing with bugs in outdated copies of the site ("have you pulled the latest version?", "I don't remember how to use git?" etc)

If there's ever a fear that I will stop paying AWS for hosting, archive.org has an image of the site that works perfectly.

Over the last few years, the directions I've put into the readme seem to have done a decent job of sorting the people who actually need an offline version from the people who simply want it, and I'm most comfortable continuing with that for the time being.

Thank you for the PR though! I appreciate the help, and please let me know if you have any other ideas for the site!