Added README Generation

[jrg94]

Because of the repo infrastructure already established in this script, I thought it would be easy to add README generation. I want to automate this because it's a huge pain in the ass by hand, and a ton of our contributors have ignored the requirement in the past—causing a lot of maintenance pain.

At the moment, my plan is to loop it into wiki generation. Probably going to rename this doc generator or something. Regardless, I think I want to use it at the pull request stage rather than the deploy stage (currently), so the updated README will show up in the pull request. You can see a working example of this in the website repo where I already do this for images.

The only catch is that any changes to the script will result in a complete update to all of the READMEs. This could be annoying with many pull requests. I think the solution at the moment is one of the following:

1. Build READMEs at deployment: I don't like this because it ruins the clean squashing that we're doing now.
2. Specify the version of the doc generator in CI: this way, we can update the version and update all READMEs at the same time.

I'm opting for the latter, and I'm thinking this will have to be implemented on the website side at some point as well.