We want to automatically derive Hash for the library settings, which
requires us to split off all the settings unused by the library
(since these shouldn't affect the hash used by ruff_cli::cache).
This makes it easier to see which rules you're enabling when selecting
one of the pylint codes (like `PLC`). This also makes it clearer what
those abbreviations stand for. When I first saw the pylint section, I
was very confused by that, so other might be as well.
See it rendered here:
https://github.com/thomkeh/ruff/blob/patch-1/README.md#pylint-plc-ple-plr-plw
This lets you test the ruff linters or use the ruff library
without having to compile the ~100 additional dependencies
that are needed by the CLI.
Because we set the following in the [workspace] section of Cargo.toml:
default-members = [".", "ruff_cli"]
`cargo run` still runs the CLI and `cargo test` still tests
the code in src/ as well as the code in the new ruff_cli crate.
(But you can now also run `cargo test -p ruff` to only test the linters.)
