Fixes a bug in the line that creates a form tag for the iframe uploader
Fixes a bug in the line that creates a form tag for the iframe uploader

This resolves an issue that was preventing IE and Opera from uploading.

FineUploader/fine-uploader,SimonWaldherr/uploader,SimonWaldherr/uploader,SimonWaldherr/uploader,FineUploader/fine-uploader,SimonWaldherr/uploader,FineUploader/fine-uploader,SimonWaldherr/uploader,SimonWaldherr/uploader,SimonWaldherr/uploader