Various maintenance 2022-01-22

[mattmccutchen]

This addresses various issues I discovered as I resumed work on #99. I'm putting all the changes in one pull request to reduce overhead; I'd be happy to make separate pull requests if that's helpful.

1. A fix for compatibility with Ruby 3, since the tests failed when I tried to run them on my Linux computer with Ruby 3.
2. Delete .ruby-version: noticed when I set up rbenv to test that (1) still worked on Ruby 2.7.
3. Raise the required Git version for Braid: noticed as I was considering what Git version #99 would need to check for.
4. Add some info to the readme about supported environments, inspired by (3). Is this OK?
   • The new readme states that we currently have no CI, which is true as far as I know because https://travis-ci.org/ (which we were using) was shut down in June 2021. We could potentially re-register the project on https://travis-ci.com/; I looked into that briefly, but it looked like I would have to grant Travis CI full access to my GitHub account, which I was unwilling to do. If we resume using Travis CI, we should review .travis.yml for anything we want to update (e.g., newer versions of Ruby). If we don't think we'll use Travis CI again, it may make sense to go ahead and delete .travis.yml. We could consider other CI services as well.
5. Make the test suite use a separate Braid cache. You'll never guess how I noticed this. The tests were slow on my Windows computer and I thought Microsoft Defender scanning might be part of the problem, so I used this tool to see what files were being scanned as the tests accessed them, and my main ~/.braid/cache showed up!

[realityforge]

Thanks!

I verified this with a few ruby 2.x versions that are still in use and on OSX and all seems fine

[mattmccutchen]

Great. I just remembered to copy the master branch to gh-pages so the readme update is visible at https://cristibalan.github.io/braid/; we still have to do that manually every time unless/until we fix #67.