Provide an artifact for the proto.

[jcchavezs]

Currently there is no straightforward way to consume the proto, the main options is either git submodule or downloading directly from github (e.g. https://gist.github.com/maboloshi/9b9a25a93b4f9a0955d1f65391c9572e). It would be better if users could consume instead fixed versions of the file rather than hashes and from a source meant to do that.

cc @pavolloffay @davexroth

[pavolloffay]

What kind of artifact would it be? zip? Published where?

I am totally fine to consume it as a git submodule or get it from GitHub e.g. via curl. We should also consider tagging/releasing it at some point (we could also upload the distro to the GH release page if there would be consumers for it).