chore(package): update css-loader to version 0.28.11

Author: greenkeeper[bot]

package.json

@@ -20,7 +20,7 @@
     "autoprefixer": "8.1.0",
     "clean-webpack-plugin": "0.1.19",
     "cross-env": "5.1.4",
-    "css-loader": "0.28.10",
+    "css-loader": "0.28.11",
     "extract-text-webpack-plugin": "3.0.2",
     "node-sass": "4.8.2",
     "postcss-loader": "2.1.1",