Added support for a progress feed.

Added a JSON feed for upload progress and session support.
Workaround for Firefox <= version 16 for file totals over 2GB.
  Reportedly fixed in FF17.

Remaining issues:
  IE8 (XP 32-bit) is still limited to 2GB uploads, possibly a browser limitation
  FF16 still will not work for file totals over 4GB.
Fixed a bug with the progress feed.

Fixed a bug with the last uploaded file not being added to the progress feed.
Added a file list and a JSON feed fix.

Fixed an issue with file names in the JSON feed.
Added a file list to the upload status page.
Some performance optimization