passing any tag name and css, styles and no key required for the ports

[hipertracker]

I created a more generic solution. It allows using any tag for the generated React node. It can also pass down classNames and styles to it. Sometimes it is important because injecting <div/> may mess with external HTML and CSS rules.

I also don't need to pass a key parameter to <Elm/> for sending changed data through ports.
https://gist.github.com/hipertracker/1423ac96662d49e432f20472478499b3