fix(package): update webpack-dev-middleware to version 3.6.1

Closes #96

Author: greenkeeper[bot]

package.json

@@ -76,7 +76,7 @@
     "vinyl": "^2.0.0",
     "webpack": "2.1.0-beta.25",
     "webpack-dashboard": "^0.2.0",
-    "webpack-dev-middleware": "^1.8.1",
+    "webpack-dev-middleware": "^3.6.1",
     "webpack-dev-server": "2.1.0-beta.10",
     "webpack-hot-middleware": "^2.13.1",
     "whatwg-fetch": "^1.0.0",