Fields example using component property or render function

### Are you submitting a **bug report** or a **feature request**?

feature request

### What is the current behavior?

The example https://codesandbox.io/s/pyrwplknom shows how a Fields component can be created.

### What is the expected behavior?

I would like to see an example using a `component` property or `render` function. Basically, replicating the `redux-form` functionality

### Sandbox Link

### What's your environment?

irrelevant

### Other information

irrelevant