Issue #72 & Issue #73

Made some minor modifications
- removed disabling "delete", so that the file can be deleted even
if the file is not uploaded - eg. cancelled
- changed mechanism to disable save button for the uploader
    - instead of checking whether a file is uploading, we check
      that the uploader's progress is 100% if the queue is more than
      1. This is so that the button stays disabled even if the file
      is cancelled (and stays on the queue)