Minor changes to stopped giving notification

I took out some unnecessary code and removed the direct deposit conditional (since direct deposits can be non-monthly).  Everything else looks almost the same as the dashboard logic.  The only question is whether to use the contact#late_by? method or not in order to avoid duplication.  @twinge do you know if there's a reason the code in this file doesn't use the contact.last_donation_date field?  I would think that would be up to date by time this code is run.