- Find out why database.py has a after_request method to remove db_session
- Fix the ugly workaround for that

+ add TODO to github bug tracker
+ extract js out of main.html & jslint & jstests
+ check test_download_expired_fails() and wrap it with unittest2.skip(), does it not work with sql backend?
* JS error if "None" is returned as maxpages, for pdf's that can't have there page  size estimated  see, "IT Landscape Germany....pdf"

* Add end to end test so we can test user stories
* Clean up expired sessions & files from these sessions (use CRON).
* Expire results from celery (using TASK_RESULT_EXPIRES)
* Check celery broker timeout
* GAE: DeadlineExceededError on building the pdf does not allow to
  save the error to the database, need another way to inform client
  that the request died
* Test fails if pre-existing database is used (not in-memory)
