fix(package): update css-loader to version 3.3.2

Closes #178

Author: greenkeeper[bot]

package.json

@@ -31,7 +31,7 @@
     "babel-preset-es2015": "^6.24.1",
     "babel-preset-react": "^6.24.1",
     "classnames": "^2.2.5",
-    "css-loader": "^2.1.0",
+    "css-loader": "^3.3.2",
     "electron": "^4.0.5",
     "electron-json-storage": "^4.0.2",
     "electron-packager": "^13.1.1",