- This is the result of running `cargo fix --edition`, with some
    manual adjustments.

  - The vast majority of changes merely qualify module paths with
    'crate::'.

  - Two instances of adding an anonymous pattern to a trait's
    function.

  - `async` is a keyword in Rust 2018, and hence it needs to be
    escaped (e.g. in the case of the net::r#async module).

  - The manual adjustments were needed due to various shortcomings of
    the analysis employed by `cargo fix`, e.g. unexpanded macros,
    procedural macros, lalrpop grammars.