Added Field for Indicating the Reason for Reservation Cancellation

A new field CancelReason has been added to the interface IReserve, containing the reason for the reservation cancellation ReserveCancelReason (ClientNotAppeared, ClientRefused, Other), or null if the reservation is not canceled.

The reservation can be canceled both through the SyrveFront application UI and via the API by calling the method CancelReserve, with the reason for cancellation specified through the reason argument. Although the ability to cancel a reservation with a specified reason is available in all supported API versions (V4+), the ability to retrieve this reason from the IReserve object has only just been introduced and will be available starting from V6/V6Preview5.