Have a bunch of benchmarks

Nobody has claimed this yet.

I every now and then do profiling of UFO loading (and writing). I think it would be nice to have a bunch of benchmarks (https://doc.rust-lang.org/cargo/commands/cargo-bench.html) ready to be run. They could also serve as entry points for profilers.

I'd say we could import a copy of Noto Sans and maybe even a custom to-UFO translation of Noto Sans CJK to have norad work up a sweat. Need to figure out the CJK part still, until the sources are opened.

Scenarios:

- Serial loading of UFOs, no parallel loading of glifs (without `rayon` feature)
- Serial loading of UFOs, parallel loading of glifs (with `rayon` feature)
- Parallel loading of UFOs, no parallel loading of glifs
- Parallel loading of UFOs, parallel loading of glifs
- Loading a single UFO without any font or glyph libs
- Loading a single UFO where every glyph has a lib with lotsa stuff and the font lib is big (to hammer `plist`)

Could also include the line-ending benches in https://github.com/linebender/norad/pull/172#issuecomment-906413066.

Start with Cargo's benchmark command and the loading scenarios listed in the issue. Define benchmark entry points for serial and parallel UFO/glif loading, large font and glyph libs, and the proposed line-ending cases from pull request 172's comment. Done means the benchmark suite covers the listed scenarios and can be run for profiling.

Written by the indexing model from the issue text.