Support platform-specific artifacts

[CrendKing]

Hello. I was doing a PR for the uv project, which trys to add a new binary which only makes sense on Windows. It is easy to only generate the binary with cargo features. However, it seems cargo-dist does not support platform-specific artifacts, which uv uses to release versions.

In this comment, Gankra laid out a suggestion of how to make it happens. It would be great if you guys can take a look and consider this feature request. If there is anything I could be of any use, please let me know.

Thank you!