one-line private method declaration gives "misindented method" error

Since `def` started returning the method name, it's been possible to define private (or protected) methods like this:

```
private def foo
  # ...
end
```

I'm not sure this is a common ruby idiom yet, but I like it. However, I noticed that sandi_meter reports this as a "misindented method", and it's counted in the summary as if it were a method over five lines.
