Sign-in sheet in progress:
1. Verified database upgrade (to add Participant table) for older
installed versions of the app.
2. Verified database access and modification for the newly added
Participant class.
3. RecordQuickParticipationActivity <-> Sign-in sheet landing page <->
Sign-in sheet flow done.
4. New sign-in sheet logic complete.
5. Modified logic of RecordQuickParticipationActivity to take into account
details already entered into a sign-in sheet.