ES6 Promise compatibility

[t3chguy]

I think this would be a lot more useful if it was compatible with promises, so instead of passing in the callback directly, you'd pass it through .then(), this way it can be wrapped directly in a promise without having to implement promises into it directly.

[JustMaier]

Sounds great. Is this something you want to tackle. I'm a little tied up with other projects at the moment.