Added Docker Support 🐳

[WillFantom]

Added Docker support in the form a Dockerfile and additions to the release workflow.

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Added a pretty basic Dockerfile to the repo and some documentation on how to run the docker version into the README. The resulting image is pretty small and seems to work on an x86 thinkpad and a m1 macbook, so imma just assume it's not too borked.

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The CI pipeline will build and push with the rest of the release workflow. Seems fine but is a little ugly since I added the bool input for latest... perhaps the release workflow should run when a tag is pushed/forced and latest set to auto?

[GeopJr]

Thanks for this PR!

I appreciate the gesture but honestly I'm unsure if it's needed. The only build dependency is crystal and the releases are already statically linked. I'm not opposed to it but it does feel like an overkill. If it's difficult to run on M1 I believe homebrew has arm builds for crystal

Either way, ideally, it should move into its own action that runs on release (https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#release) since the release workflow only creates a draft (on purpose, so I write the changelog & do last second testing)

[WillFantom]

I appreciate the gesture but honestly I'm unsure if it's needed. The only build dependency is crystal and the releases are already statically linked. I'm not opposed to it but it does feel like an overkill. If it's difficult to run on M1 I believe homebrew has arm builds for crystal

Hey, for me at least its more for package mgmt reasons... There's something nice about running a cmd that'll do the install as and when needed (and knowing a docker system prune -a will be a nice cleanup now and then)

+ It's not all that much extra to maintain I guess? (that said, keeping make in the build stage does kinda make it even easier to maintain)

Happy to make more changes though if can move towards a merge

[GeopJr]

I'll move forward with it, thanks!