- Updated paragraphs and wording for clarity.
- Renamed `helloworld.rs` to `myprogram.rs` to make it clearer that it's an unrelated example.

This is about the gray area at the top of a trait's documentation page,
that lists all methods and their signatures. A big trait page like
Iterator is very crowded without this tweak.

This doesn't actually do anything for LLVM 4.x yet, but sets the stage.

Docs: Update to "Getting Started" section

I came across rust-lang#34523 and wanted to suggest a solution. See commit for details.

It seemed like a good place to start contributing, let me know if I did anything wrong 😇

…r=nrc

parser: support paths in bang macro invocations (e.g. `path::to::macro!()`)

r? @nrc

Unify `TokResult` and `ResultAnyMacro`

Fixes rust-lang#36641.
r? @nrc

…bnik

rustdoc css: Put `where` in trait listings on a new line

This is about the gray area at the top of a trait's documentation page,
that lists all methods and their signatures. A big trait page like
Iterator is very crowded without this tweak.

reject macros with empty repetitions

Fixes rust-lang#5067 by checking the lhs of `macro_rules!` for repetitions which could match an empty token tree.

…rner

E0513

Part of rust-lang#35233

r? @jonathandturner

…richton

Extend preprocessor LLVM version checks to support LLVM 4.x

This doesn't actually do anything for LLVM 4.x yet, but sets the stage.

…dturner

New error format for E0512

Part of rust-lang#35233, fixes rust-lang#36107

r? @jonathandturner