The Bulk File upload UI is difficult to use. Large file uploads raise "script is unresponsive" alerts. It is unclear to users if bulk file upload is working. Errors are not displayed nor is a success message always shown when an upload is successful.

Specific problem example:

A user was able to submit a bulk file upload request with no files selected. This, most likely, caused the browser to send a request with no files request attribute.

There was an Internal Server Exception generated because of a null pointer exception in the FileUploadFormFilesRequiredValidator class.

Acceptance Criteria:

Report progress of individual file uploads in Bulk Upload UI.

Suggestions:
Disable the Upload Button after it is clicked.
A file upload can be in the states: New, Waiting, In Progress, Complete, Error.