Allow uploaders to reset the iFrame embed to upload more files
Currently, if an uploader adds files one at a time to the iFrame embed, it will prevent adding more files once the first file is uploaded...the workaround is to let the user know that they have to refresh the entire page the embed is on.
There are a few ways to solve this:
* Very, very quick: add a link to the iframe completion page of ("Upload more files") that simply refreshes the page inside the iframe
* Don't replace the upload dropbox with the progress bar or completed files so it's always visible.