Update electron and electron-packager

Author: hidakatsuya

package.json

@@ -16,8 +16,8 @@
   "devDependencies": {
     "cross-env": "^5.0.5",
     "del": "^3.0.0",
-    "electron": "^1.6.10",
-    "electron-packager": "^8.7.0",
+    "electron": "^1.6.11",
+    "electron-packager": "^8.7.2",
     "electron-prebuilt": "^1.4.13",
     "js-yaml": "^3.9.1"
   }