Spec Notify mailers
Created by: robbkidd
Add spec for Notify ActionMailer class and update mailer methods to be queue-friendly.
The MailerObserver class is the only consumer of Notify and remains unspec'd. I started in on specs for it, but they got hairy quickly because MailerObserver knows about lots of things and has a fair amount of branching logic. Absent these specs for the moment, I did my best to update the calls to the Notify methods to use IDs as parameters.
With the number of changes already in this branch, I reckon it would be good to submit it for review even if you find that it is not ready to merge.
Related to code and commentary in pull requests #813 and #820