message: back to webdev server - 2.11
diff: "typings": "2.1.1",
  "web-animations-js": "2.3.1",
  "webpack": "3.11.0",
  - "webpack-dev-server": "3.1.2",
  + "webpack-dev-server": "2.11.1",
  "webpack-merge": "4.1.2",
  "zone.js": "0.8.20"
  },
  