Widen ash support up to 0.37, and bump version to 0.13.1.

[eddyb]

As explained in the comment left in Cargo.toml, we can support multiple (otherwise "breaking") versions of ash, because very little of ash's API surface is being interfaced with.

I've tested the code with ash at 0.35, 0.36, 0.37 and they all pass cargo check, but I don't have a macOS system to test that it actually runs - still, the API is so simple I can't imagine it breaking in a subtle way.

Since this is backwards-compatible, I've only bumped the patch number in ash-molten's version, and we can continue to do so in the future to support more ash versions.

Something I'm not sure about is: should CI try all supported ash versions to avoid regressing?

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As for why I need this: bumping wgpu in Rust-GPU, for example-runner-wgpu, requires ash 0.37, and ash-molten was keeping example-runner-ash on ash 0.35, leading to two builds of ash (it's not the only cause of build duplication, but it was getting in the way).

With this PR, I can unify those dependencies quite nicely (though, again, can't actually test native functionality on macOS).

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Also, whoever lands this PR should publish the new version (I don't think I have the power to, but also I'd rather not touch that part).

[eddyb]

Interesting, looks like the proc macro ecosystem now requires Unicode-DFS-2016 (via unicode-ident).
That seems harmless but I am very much not a lawyer. For the record this is the PR adding it:

• Explain Unicode license agreement dtolnay/unicode-ident#9

And you can see below that all the repos using cargo-deny which have had to allow the new license.

[MarijnS95]

Thanks, yeah, that's how I intended this to be used. Allows ash-molten to do a simple patch release as well as long as the lower bound for ash doesn't change 🎉