version in production throws invalid isbn exception
made sure you can't delete an id if the edition is left id-les
fixed bug where using an existing id omits admin setting
NOTE MIGRATION needed
* Immediate reason for this implementation is to make it harder for our AWS keys to be compromised -- this will allow us to store them in encrypted (AES 256) form in the db, which will require ability to run mysql on the EC2 instance
* depends on a Django settings.SECRET_KEY, which for now, we might store in settings/local.py -- we could get fancier about how to serve that up
One overrides regluit.utils.localdatetime._now to do "time travel" -- useful for testing scenarios requiring time changes (such as Campaigns)
Get rid of call references to datetime.datetime.now() or utcnow() and datetime.date.today() in favor of regluit.utils.localdatetime.now() and date_today().