Feature request: pass down the original event to the onChange handler

[mgcrea]

Coming from react-toolbox, one pattern I really liked to use is to rely on the name prop of the control to easily know inside the handler from which control it has been called. Just like what we can do with the HTML name prop.

It enables complex forms to have a single onInputChange handler that is really clean and efficient:

  handleInputChange = (value, ev) => {
    this.setState({[ev.target.name]: value});
  }

However it requires the original event.target to get back the HTML name prop. Usually passed as the last argument to the onChange handler;

Do you think the event could be passed as a third argument to allow such workflow in a non-breaking way?

I will gladly provide a PR with unit test if you agree on the changes.

[yesmeck]

We already pass Option as the second argument to onChange.