OTRSP command control (N1MM and other logging programs)

I have implemented a small part of the OTRSP protocol. OTRSP was primarily developed to support SO2R operation for contesters using 2 radios. SO2R boxes switch resources like headphones, microphone, keyer, and logging focus via commands from a logging program such as N1MM+.

SO2R is single Operator, 2 Radios. SO2V is Single operator, 2 VFO (Like a dual receiver radio). SO1V is one operator and 1 VFO.

I have tested only with N1MM+ so far. N1MM has a Antennas table letting you define in a very flexible way relationships between radio bands and antennas along with some other things like rotator control. It supports 2 radios in SO2R, SO2V and SO1R setups.

When you use the program to change bands the table is consulted to find a row that has the matching band and sends out over a serial port the row number. It is currently limited to 1`6 rows over serial, 64 rows over the network.

See the Band Decoder Translation Modes Wiki page for details about how OTRSP commands from radio 1 (AUX1) and Radio 2 (AUX2) are leveraged.

In this project AUX1 is mapped to output ports A and B, AUX2 to Port C. They may be utilized exclusively or ignores based on the chosen Translation Mode.