Create attendance mailer
Mailers no longer deliver by default per dj recs
Allow ActiveMailer Deliveries to be Cancelled

ActionMailer is dumb. You can't return anything other than a mail
EVEN THOUGH IT SAYS YOU SHOULD BE ABLE TO. This lets you call the
method `cancel_delivery`to cancel delivery of a message and exit
from the processing of that mail
Use DelayedJob in Testing

Add ActiveRecord observers and hook into the after_create for DelayedJob
to force execution of an immediate job just after it is persisted.