fix calendar broken

vendor/built_in_modules/calendar/calendar.json

@@ -0,0 +1,14 @@
+{
+  "title": "calendar",
+  "version": "0.1",
+  "organization": "Rulingcom",
+  "author": "Visual dep",
+  "intro": "A simple and amazing calendar",
+  "update_info": "Some info",
+  "create_date": "11-08-2012",
+  "app_pages":  ["calendar"],
+  "widgets": [],
+  "category": [],
+  "widget_fields":[],
+  "enable_frontend": true
+}