Update Factories with new traits to simplify test setup
Rewrite Followup Mailer to work with custom job

Moves control of grouping outside of ActionMailer, where it doesn't work as expected.
Custom processor for tea time followup
Fix botched rebase that broke flaking reasons
Make attendance marking validation less strict
Merge branch 'custom-tt-jobs' into attendance

This provides the logic for sending followup emails after attendance
has been marked.
Only send Ethos mail when user hasn't been to a TT
Marking works across the board
Send followup emails once attendance has been marked