fix(export): fix export dashboard to json, been broken in master for 2-3 weeks

public/app/grafana.ts

@@ -1,6 +1,7 @@
 ///<reference path="headers/common.d.ts" />
 
 import 'bootstrap';
+import 'vendor/filesaver';
 import 'lodash-src';
 import 'angular-strap';
 import 'angular-route';