Prepare crates io release

[steckes]

No description provided.

[mgeier]

We should maybe stress that this is for patching an already compiled library (what the "thirdparty" name already hints at), not for patching the library that's currently built.

I was a bit confused by this ...

[steckes]

Is this too long?

Use it in your `build.rs` to patch an **already compiled external static library**
before linking it into your crate. In the example below, `vendor/libthirdparty.a`
must already exist.

This does **not** patch the library produced by the current crate: Cargo runs
`build.rs` before compiling that crate, so its output library is not available yet.
To patch your own crate's static library, first build it, then use the
[CLI tool](#as-a-cli-tool-post-build) as a separate post-build step.

[mgeier]

I like it!

[mgeier]

I'm not sure if caching is even necessary in quality.yml. I might save a few tens of seconds while not being the bottleneck. OTOH, the workflow file gets simpler when dropping all the cache-related stuff.