Run cargo fmt and fix documentation tests

[haighcam]

I disagree with how cargo fmt handles some of the chains. If you are going to format it please use chain_width = 100.

[JCapucho]

I can remove the formatting changes and just keep the documentation fixes if you want

[haighcam]

Sure that works for me. Though I would probably still end up running cargo fmt myself since I like most of the formatting it does (just not how it handles chains by default).

[haighcam]

I added a rustfmt.toml with the settings I would like for cargo fmt, so if you pull that and rerun cargo fmt then it should be good to merge.

[JCapucho]

I've rebase and reran cargo fmt, let me know if it's good now.

[haighcam]

Thanks, looks good.