Unable to find section style in .yapf.style

It says in help that

```
--style-help show style settings and exit; this output can be saved
to .style.yapf to make your settings permanent
```

so I did

```bash
yapf --style-help > ~/.style.yapf
```

but it yielded error

```
yapf: Unable to find section [style] in $HOME/.style.yapf
```

This workaround fixes the issue:

```
yapf --style-help > tmp && mv tmp ~/.style.yapf
```

However, I feel it'd be of better user experience if this could be somehow improved. Thank you so much!