default to running with `--in-place` in pre-commit hook

[graingert]

trafficstars

[spookylukey]

At the very least the hook should pass -c argument so that you get notified of issues.

The current behaviour of the hook without arguments is that it always prints:

autoflake................................................................Passed

Which is not very helpful :-)

But I'd also prefer defaulting to --in-place - given the tool is about automatically making changes. If I just want notifications, then I can use flake8 as a commit hook.

[max-sixty]

Agree — would it be reasonable to have the suggested entry at https://github.com/myint/autoflake/pull/62#issue-552588261 be the default?