message: State that rustup uses this crate
diff: //!
  //! See also the [`dirs`](https://docs.rs/dirs) crate.
  //!
  -//! _Note that as of 2019/08/06 it appears that cargo uses this crate, but
  -//! rustup does not._
  +//! _Note that as of 2019/08/06 it appears that cargo uses this crate. And
  +//! rustup has used this crate since 2019/08/21._
  //!
  //! The definition of `home_dir` provided by the standard library is
  //! incorrect because it considers the `HOME` environment variable on
  