Parse all valid arguments accepted by GNU diff to request a unified c… #24

Job	Run time
cargo fmt --all -- --check	12s
cargo check (ubuntu-latest)	15s
cargo clippy -- -D warnings (ubuntu-latest)	16s
Code Coverage (ubuntu-latest, unix)	1m 13s
cargo check (macOS-latest)	31s
cargo clippy -- -D warnings (macOS-latest)	21s
GNU test suite	39s
Code Coverage (macos-latest, macos)	1m 10s
cargo check (windows-latest)	51s
cargo clippy -- -D warnings (windows-latest)	48s
Code Coverage (windows-latest, windows)	53s
cargo test (ubuntu-latest)	52s
cargo test (macOS-latest)	1m 13s
cargo test (windows-latest)	53s
	10m 7s

Provide feedback