SAK-41021 - Date/Time screens for Signup events: confirmed and (#6378) waitlisted
Commit to register and show the date and time in which a student signed up to event. This information is also shown in exported Excel files. Order in both Inscription (by name) and Waiting (by list_index) lists is not modified.
(cherry picked from commit bd9846d1f8873cb41fcb47c92986e599d2638935)