Small cleanups, disable buttons during processing
Generate zipfile async so status can be updated.
Use generator/consumer model for processing entries

Make status messages appear correctly.
Can be extended to allow cancel button.
Add a final message when zip is complete
Merge branch 'fileGenerator' into gh-pages

This improves the feedback while files are being scanned.

* fileGenerator:
  Add a final message when zip is complete
  Use generator/consumer model for processing entries
  Generate zipfile async so status can be updated.