Add a Dockerfile
Hi,
Just found out your language after your advertised it on Reddit.
For trying it out, tt could be nice to add a .Dockerfile that can be used to have a working installation of Inko without having to install Rust/Ruby on my machine and/or mess with my existing setup. Especially, it seems to require make which is not installed by default on Windows.
I would probably do a PR for this in the following days since it looks trivial considering the small set of dependencies.