IEEE 802.11ay First Release

The release includes the following new features:

1. IEEE 802.11ay-compliant MAC and abstracted PHY layer implementation.
2. Advanced beamforming techniques (EDMG BRP PPDU and short SSW frame).
3. SU-MIMO beamforming training and channel access procedure for data transmission.
4. MU-MIMO beamforming training procedure.
5. Channel bonding up to four channels.
6. Channel transmit masks for all channel configurations in IEEE 802.11ay.
7. MIMO ray-tracing channel interface.
8. Re-based the current implementation to ns-3.31.