fix(package): add trailing comma

Author: niieani

package.json

@@ -43,7 +43,7 @@
     "awesome-typescript-loader": "^2.1.0",
     "babel-core": "^6.14.0",
     "babel-polyfill": "^6.13.0",
-    "babel-preset-es2015": "^6.14.0"
+    "babel-preset-es2015": "^6.14.0",
     "regenerator-runtime": "^0.9.5"
   },
   "peerDependencies": {