Function event_of 

pub fn event_of(
    task: &Task,
    time: Option<(i64, i64)>,
    today: Date,
    zone: &TimeZone,
) -> EventEdit

The event form of a task made an appointment: at time (time_of); without one, on its day to start, else its date asked, else today, at 9:00 for an hour, for the person to say.