* Select channel type by enum instead of three boolean
* ASCI: Add assignment to a VGCS/VBS channel
* ASCI: Send release on VGCS/VBS channel via unit data
* ASCI: Add support for reception of TALKER/LISTENER DETECTION
* ASCI: Indicate release of subscriber connection to VGCS FSM
* ASCI: Forward lchan activation states to VGCS FSM
* ASCI: Forward RLL to VGCS FSM
* ASCI: Add decoding of VGCS/VBS A-interface messages
* ASCI: Add processing and FSMs for VGCS/VBS
* ASCI: Add encoding of VGCS/VBS A-interface messages