rust: move rustfmt.toml to repo root so it can be used by `hg fix` `hg fix` runs the formatters from the repo root so it doesn't pick up the `rustfmt.toml` configs we had in each the `hg-core`, `hg-cpython`, and `rhg` packages, which resulted in warnings about `async fn` not existing in Rust 2015. This patch moves the `rustfmt.toml` file to the root so `hg fix` will use it. By putting the `rustfmt.toml` file in a higher-level directory, it also applies to the `chg` and `hgcli` packages. That makes `test-check-rust-format.t` fail, so this patch also applies the new formatting rules to those packages. Differential Revision: https://phab.mercurial-scm.org/D9142

// Copyright 2018 Yuya Nishihara <yuya@tcha.org>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.

mod attachio;
mod clientext;
pub mod locator;
pub mod message;
pub mod procutil;
mod runcommand;
mod uihandler;

pub use clientext::ChgClient;
pub use uihandler::{ChgUiHandler, SystemHandler};