Document `--dump-default-config` in README.md
Fixes
@@ -208,7 +208,8 @@ options covering different styles. File an issue, or even better, submit a PR.
```
* When you run rustfmt, place a file named `rustfmt.toml` or `.rustfmt.toml` in
target file directory or its parents to override the default settings of
- rustfmt.
+ rustfmt. You can generate a file containing the default configuration with
+ `rustfm --dump-default-config rustfmt.toml` and customize as needed.
* After successful compilation, a `rustfmt` executable can be found in the
target directory.
* If you're having issues compiling Rustfmt (or compile errors when trying to
