Auto merge of #75169 - ehuss:update-cargo, r=ehuss

Update cargo

8 commits in 2d5c2381e4e50484bf281fc1bfe19743aa9eb37a..1653f354644834073d6d2541e27fae94588e685e
2020-07-31 21:56:08 +0000 to 2020-08-04 23:14:37 +0000
- Fix close_output test. (rust-lang/cargo#8587)
- clippy fixes, use matches! macro in more places (rust-lang/cargo#8575)
- Display embedded man pages for built-in commands. (rust-lang/cargo#8456)
- Add mdman for generating man pages. (rust-lang/cargo#8577)
- Fix typo 'more then' -> 'more than' in error and comments (rust-lang/cargo#8581)
- cargo login: make login message less ambiguous (rust-lang/cargo#8579)
- Fix broken link in Build Cache chapter. (rust-lang/cargo#8578)
- Fix intra-doc tests for renamed lint. (rust-lang/cargo#8576)