Rust

Improve docs for `ViewportCommand` #46

Job	Run time
Format + check + test	10m 49s
Check wasm32 + wasm-bindgen	2m 24s
android	40s
cargo-deny aarch64-apple-darwin	40s
Check Windows	1m 39s
cargo-deny aarch64-linux-android	40s
cargo-deny i686-pc-windows-gnu	55s
cargo-deny i686-pc-windows-msvc	1m 4s
cargo-deny i686-unknown-linux-gnu	39s
cargo-deny wasm32-unknown-unknown	52s
cargo-deny x86_64-apple-darwin	39s
cargo-deny x86_64-pc-windows-gnu	48s
cargo-deny x86_64-pc-windows-msvc	40s
cargo-deny x86_64-unknown-linux-gnu	39s
cargo-deny x86_64-unknown-linux-musl	39s
cargo-deny x86_64-unknown-redox	54s
	24m 41s

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