HOC should pass props?

Thanks for a great tool!

I think the [expected behaviour](https://reactjs.org/docs/higher-order-components.html#convention-pass-unrelated-props-through-to-the-wrapped-component) for a HOC is to pass external props through untouched, which I notice the `withLive` component doesn't. Would you be open to adding it, or is there a reason not to?
