Plugin API - CSS Preprocessors

[insin]

How much magic do we really want here?

Thinking about CSS preprocessors, It would be nice if you could just install an nwb-sass, nwb-less etc. package which would hook these up with default pipelines for static and server builds like CSS currently has. So a bit of package.json scanning for those.

All they really need to provide is a unique name and test and loader config (absolute path to a dependency owned by the plugin). What if this was the entire nwb-sass plugin?

module.exports = {
  cssPreprocessor: {
    sass: {
      test: /\.scss$/,
      loader: require.resolve('sass-loader')
    }
  }
}

We could potentially use whatever hook we add for this to allow the user to configure and manage their own preprocessor dependencies.

#564