sorting Rust crates [was Re: rav1e AV1 encoder]

[Leo Famulari]

On Fri, Feb 21, 2020 at 04:15:43AM -0500, Martin Becze wrote:
> sort2.scm will sort a files exported packages alphanumerically.

I'm working on packaging rav1e for Guix again and so I'm using sort2.scm
on the big 'gnu/packages/crates-io.scm' module.

One problem I noticed with sort2.scm is that inherited packages need to
be after the package they inherit from, but this means they will not be
alphanumerically sorted.

For example, sort2.scm will put rust-bytes-0.3 before rust-bytes-0.4,
but then the build fails, because the former inherits from the latter
but can no longer find it.