Email verification and forgot password verification tokens should expire

[Christopher Allan Webber]

Email verification should expire after 30 days and forgot password verification should expire after 7.

Things that should be done:

• These fields should be added but not required
• Views should be modified to add these expiration fields when adding the tokens
• Views should be modified to check the expiration fields before using
• A migration should be added...
  • fields without verification keys should just have the email_verification_expires and/or fp_verification_expires set to None
  • fields with verification keys should set them to a timedelta from today

You can set these fields via a timedelta:

>>> import datetime
>>> datetime.datetime.now() + datetime.timedelta(days=10)
datetime.datetime(2011, 7, 4, 8, 41, 8, 502139)