Support for chroma-js 2 and dart-sass

[tim-janik]

Hi, I have a need for chroma.js v2 support and dart-sass support (the sass npm module, used by e.g. rollup-plugin-vue, instead of node-sass).

So I have started work on an ES version of chromatic-sass2.js, based on: https://github.com/bugsnag/chromatic-sass/blob/master/src/main.coffee

I'd like to know whether that is something you would like to integrate into this project.

Or, if you recommend I investigate npm module releases and better do a chromatic-sass-2 npm module release myself.

The start of mywork can be found here: https://github.com/tim-janik/beast/commit/3cca5c4d4a3ff3536eedd861016586ce1392916f