message: Tweak wording for config.md
diff: @@ -613,7 +613,7 @@ Sets the path to the root directory for installing executables for [`cargo
  install`]. Executables go into a `bin` directory underneath the root.
  To track information of installed executables, some extra files, such as
  -`.crates.toml` and `.crates2.json`, would also be created under this root.
  +`.crates.toml` and `.crates2.json`, are also created under this root.
  The default if not specified is Cargo's home directory (default `.cargo` in
  your home directory).
  