add `bevy new` use facing documentation #445

Job	Run time
Check for typos	4s
extract-rust-version / Extract Rust version	3s
Check with rustfmt	19s
Check with Clippy	44s
Build docs	42s
Run tests (ubuntu-latest)	1m 8s
Run tests (windows-latest)	4m 29s
Run tests (macos-latest)	1m 29s
	8m 58s

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