CampTix: Add automatic emails to attendees requesting details about their accessibility accommodation or life-threatening allergy

[CdrMarks]

The proposal to automatically send emails to WordCamp attendees requesting details about their accessibility accommodation or life-threatening allergy received support from all those who replied. This issue is to track the work to add this functionality.

E-mail Templates: [ ] Add template requesting details about an attendee's accessibility accommodation [ ] Add template requesting details about an attendee's life-threatening allergy

Attendee E-mails: [ ] Add e-mail requesting details about an attendee's accessibility accommodation [ ] Add e-mail requesting details about an attendee's life-threatening allergy

[hellojuliarose]

When implementing this, let's use the term severe allergy rather than life-threatening allergy.