* @cfg {String} url Location to download from.
* @cfg {String} method GET or POST (default GET), POST will create a form, and post that into the hidden frame.
* @cfg {Boolean} newWindow (optional) download to new window
+* @cfg {Boolean limit (optional) limit for grid downloads.
+
* @cfg {Function} success (optional) MAY fire on download completed (fails on attachments)..
* @cfg {Number} timeout (optional) in milliseconds before it gives up (default 30000 = 30s)
* @cfg {Roo.grid.Grid} grid (optional) if you want to just download a grid, (without renderers..)