[rustdoc] Add new setting to wrap source code lines when too long Fixes https://github.com/rust-lang/rust/issues/127334. Wrapped lines look like this:  It works in both source code pages and doc pages. You can test it [here](https://rustdoc.crud.net/imperio/code-wrapping/bar/index.html). r? ``@notriddle`` |
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| build.rs | ||
| Cargo.lock | ||
| Cargo.toml | ||
| lib.rs | ||
| macros.rs | ||