Added support for producing distribution archives

[UebelAndre]

This change introduces the //distro:rules_rust target which produces a minimal archive of rules_rust. This archive is one of the final stepping stones to closing out #415 which is something I'd like to see done this week. This PR is required by #1195 which updates the release workflow to produce this new tar archive as a release artifact for easy user consumption.

[hlopko]

Looks good to me, thank you!

One question though. Right now we release everything in rules_rust, including experimental things and things not covered by the compatibility policy. Alternative approach would be to only release stable stuff and ask users who need more to use HEAD. That would emphasize that they are using something not well supported.

I think I'm fine either way, I just wanted to make sure there was a discussion about this.

[illicitonion]

LGTM!

One question though. Right now we release everything in rules_rust, including experimental things and things not covered by the compatibility policy. Alternative approach would be to only release stable stuff and ask users who need more to use HEAD. That would emphasize that they are using something not well supported.

I think I'm fine either way, I just wanted to make sure there was a discussion about this.

Also fine either way :)

[UebelAndre]

One question though. Right now we release everything in rules_rust, including experimental things and things not covered by the compatibility policy. Alternative approach would be to only release stable stuff and ask users who need more to use HEAD. That would emphasize that they are using something not well supported.

I think I'm fine either way, I just wanted to make sure there was a discussion about this.

I think experimental things are fine to include in an archive like this. We should not have something missing from the compatibility policy (even if it's just saying we're ignoring it). I like the idea that release artifacts are by Bazel so if we wanted to have an artifact with no experimental rules, I'd have thought that'd be a separate release artifact, much like the "core" package from rules_nodejs releases. For now though, I'd prefer to include experimental things in the release unless there's a need to downsize.

@hlopko does that sound reasonable?

[UebelAndre]

Gonna merge for the time being but am happy to continue the discussion and make changes so everyone's happy.