Implement absolute color conversions and chromatic adaptation #506

Job	Run time
cargo clippy (wasm32)	25s
formatting	29s
cargo check (msrv) (wasm32)	20s
cargo check (msrv) (windows-latest)	36s
cargo doc	12s
cargo check (msrv) (macos-latest)	21s
cargo clippy (windows-latest)	53s
cargo miri	1m 46s
cargo check (msrv) (ubuntu-latest)	16s
cargo test (windows-latest)	49s
cargo test (wasm32)	13s
cargo test (macos-latest)	22s
cargo clippy (macos-latest)	30s
cargo test (ubuntu-latest)	16s
cargo clippy (ubuntu-latest)	29s
typos	4s
	8m 1s

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