message: upgrade electron version to 2.0.4
diff: "bluebird": "3.5.1",
  "browserify": "16.2.2",
  "cross-env": "5.2.0",
  - "electron": "2.0.3",
  + "electron": "2.0.4",
  "electron-builder": "20.16.4",
  "electron-builder-squirrel-windows": "12.3.0",
  "electron-chromedriver": "2.0.0",
  