add adminUsername on app.conf

conf/app.conf

@@ -6,6 +6,9 @@ http.port=9000
 
 site.url=http://localhost:9000 # or http://x.com:8080, http://www.xx.com:9000
 
+# admin username
+adminUsername=admin
+
 # mongdb
 db.host=localhost
 db.port=27017