feature_request(repl.it): support Stylus

[Kristinita]

1. Summary

It would be nice, if Repl.it will support Stylus CSS preprocessor.

2. Argumentation

I can use Stylus in Codepen.io, but Codepen doesn't support more than one project (multiple files) for free plan.

It would be nice, if Repl.it users will have the opportunity use multiple Stylus files for repls. It a reason for Stylus users migrate from Codepen to Repl.it.

Thanks.