Add Webpack Stylus loader

package.json

@@ -47,6 +47,7 @@
     "stylelint": "^10.1.0",
     "stylelint-config-recommended": "^2.2.0",
     "stylus": "^0.54.5",
+    "stylus-loader": "^3.0.2",
     "webpack": "^4.35.2",
     "webpack-cli": "^3.3.5",
     "webpack-dev-server": "^3.7.2",