Update electron to the latest version 🚀 (#69)

* chore(package): update electron to version 1.8.3

* chore(package): update lockfile

https://npm.im/greenkeeper-lockfile

Author: greenkeeper[bot]

package-lock.json

@@ -83,7 +83,7 @@
   },
   "devDependencies": {
     "clean-css": "4.1.11",
-    "electron": "1.8.2",
+    "electron": "1.8.3",
     "electron-builder": "20.2.0",
     "electron-rebuild": "1.7.3",
     "node-json-minify": "1.0.0",