Feature request: ability to specify multiple dist resolutions

**I'm submitting a feature request**

* **Library Version:**
3.0.0

At the moment, we can only specify 1 distribution format, but it would be nicer if we can instruct webpack to resolve multiple distributions in order. For example, I'd like to resolve to es2017 then es2015 then native-modules, as async await is broadly available in modern browsers.