Suggestion: Workflow for creating WASM files

[Mqxx]

Hey, I recently came across this project through denosass and I think it's great. I would like to use grass in combination with ESBuild. But for that I would need the WASM bindings for JavaScript. Personally, I don't really have any experience with Rust (only a little bit about WASM) and the bindings that @hironichu created back then are now over 2 years old. I guess a lot has changed in that time, as many features have been added by grass.

So it would be really cool to add a workflow that automatically creates WASM bindings after a release, this would also greatly increase the range of applications.

With that said, keep up the good work! This project is great!

~Mqx