Provides methods and attributes relating to appointments.

The following operations are supported. For a formal definition, please review the Service Description.

• AddOrUpdateAppointments
  Adds or updates a list of appointments.
• AddOrUpdateAvailabilities
  Adds or updates a list of availabilities.
• GetActiveSessionTimes
  Gets a list of times that are active for a given program ID.
• GetAppointmentOptions
  Gets a list appointment options.
• GetBookableItems
  Gets a list of bookable items.
• GetScheduleItems
  Gets a list of scheduled items (appointments, availabilities, and unavailabilities).
• GetStaffAppointments
  Gets a list of appointments that a given staff member is instructing.