Physicallayer: followed the recent signal analog model changes.
ReceptionDecision: added packetModel.
NarrowbandReceiver, Transmitter, APSKScalarTransmitter: modulator->modulation, currently there is no QAM256.
Ieee80211LayeredReceiver, LayeredReceiver: followed recent RadioMedium changes.
Ieee80211ScalarTransmitter: modulator->modulation.
Receivers: ReceptionDecision: packetModel = NULL.
Ieee80211LayeredScalarRadioMedium: changed analogModelType.
LayeredReception: renamed to LayeredScalarReception.
LayeredSNIR: deleted.