Add a script to generate API files using `cargo public-api` for the
crates that we are trying to stabalise (the so called 'leaf crates').
- hashes
- io
- primitives
- units
We already ran the script and committed the files last patch. The fact
that this patch does not include any changes to the `api/` directory and
that CI passes is enough to convince us that last patch was valid.
Add a CI job that runs the script and checks there are no changes to
the committed text files thereby proving no API changes are made in a
PR without explicitly modifying the API text files.
Add documentation to `CONTRIBUTING.md` on what is expected of devs.
We would like to check for API changes during development and in CI so
that such changes can be discussed separately from the code.
Add tooling and documentation for creating API listings for the public
crates within the workspace (i.e., not `internals`).
Add API text files from an initial run of the script.
Jose Storopoli
Tobin C. Harding
Jose Storopoli