fix(package): add missing comma

Author: Awk34

templates/app/_package.json

@@ -53,7 +53,7 @@
     "@angularclass/hmr-loader": "^3.0.4",
     "reflect-metadata": "^0.1.3",
     "rxjs": "^5.5.2",
-    "zone.js": "^0.8.12"
+    "zone.js": "^0.8.12",
     "@angular/common": "^5.0.1",
     "@angular/compiler": "^5.0.1",
     "@angular/core": "^5.0.1",