[router] Add some comments in adapter
[router] Add some comments in adapter

jvanmalder/ttn,jvanmalder/ttn,TheThingsNetwork/ttn,LoRaWanSoFa/ttn,mgranberry/ttn,LoRaWanSoFa/ttn,TheThingsNetwork/ttn,mgranberry/ttn,mgranberry/ttn,jvanmalder/ttn,TheThingsNetwork/ttn