Auto merge of #4400 - behnam:pr4157, r=alexcrichton

Auto merge of #4400 - behnam:pr4157, r=alexcrichton

[check|build|rustc] Add --all-targets option

`cargo check` does not check all targets by default, and to check all,
you need to call it `cargo check --tests --examples --bins --benches`.

Here, we implement `--all-targets` For `check`, `build`, and `rustc`.

For consitency, `--all-targets` is also added to other commands like
`test` although "all targets" is the default behavior.

This is a rebase of <https://github.com/rust-lang/cargo/pull/4157>