enableStylusLoader(stylusLoaderOptionsCallback = () => {}) {
        webpackConfig.enableStylusLoader(stylusLoaderOptionsCallback);

        return this;
    }
Call this if you plan on loading stylus files.

```
Encore.enableStylusLoader();
```

Or pass options to the loader

```
Encore.enableStylusLoader(function(options) {
    // https://github.com/shama/stylus-loader
    // options.import = ['~library/index.styl'];
});
```

@param {OptionsCallback<object>} stylusLoaderOptionsCallback
@returns {Encore}