Queue widget fixed to handle errors returned by jsonrpc

Modified jquery.plupload.queue.js to handle errors returned via jsonrpc.

I must modify the class, because i could not extend it.
So i have changed

• handleStatus function (line:104-135)
• and also FileUploaded and UploadProgress event handlers which invokes handleStatus (line:318-328)

Files are uploaded to upload.php which always returns error in jsonrpc format

Tested only under flash runtime