Created by Tomas Bajarunas, last modified on 2019.04.23
INTEGER Allows to separate counting transfers from
transfer application is invoked,
max_forwards is decremented.
max_session_transfers variable is set in a channel,
max_forwards is not touched when
transfer application is invoked and
max_session_transfers value is decremented instead.
This can be used to prevent calls going on-hook in larger IVR applications when many transfers are expected.