Add CI for building binaries

[RangerMauve]

It'd be useful to be able to distribute the utility without requiring that folks set up node.js and NPM and go through all that rigamaroll.

Ideally people should be able to go to the releases page and download the latest version + run it locally.

This might also be useful down the line for integrating with package managers like apt (or one of the billions of Linux alternatives).

Here's a utility that can help: https://github.com/vercel/pkg

A PR for a Github Action would be very much welcome.