Serial protocol changed to allowing controller to know if an incoming message is a ack. Outgoing and incoming serial messages now also have the same parameter count.

radioId;childId;messageType;ack;subType;payload\n

Where ack parameter means the following:
outgoing: 0 = unacknoledged message,  1 = request ack from destination node
Incoming:  0= normal message, 1=This is an ack message