chore(package): update webpack-dev-middleware to version 3.1.0

Closes #45

Author: greenkeeper[bot]

package.json

@@ -70,7 +70,7 @@
     "typescript": "^2.1.4",
     "url-loader": "^0.5.7",
     "webpack": "^1.13.0",
-    "webpack-dev-middleware": "^1.6.1",
+    "webpack-dev-middleware": "^3.1.0",
     "webpack-hot-middleware": "^2.10.0",
     "webpack-manifest-plugin": "^1.0.1",
     "yargs": "^6.5.0"