This is a CLI tool to read and write configuration parameters to a Brain 2 FBL
unit from either Linux or (untested, but in principle...) macOS.

The Brain shows up as some kind of tty serial device (typically /dev/ttyUSB0 on
Linux, something wordier on macOS), which must be passed to the script as a
positional argument.

A configuration parameter you want to see or modify is a two-level entity, with
a namespace of either "global", "setup1", "setup2", or "setup3". Global and
setup have differing permitted fields (listed in fields.py).

When writing, the value is a 16-bit integer which may be given in either decimal
or hexadecimal form.

Example usages:

$ ./brain-config.py /dev/ttyUSB0 --read global.GovDiv
global.GovDiv: 2100

$ ./brain-config.py /dev/ttyUSB0 --write global.GovDiv=42
global.GovDiv: 2100 -> 42

$ ./brain-config.py /dev/ttyUSB0 --write global.GovDiv=0x834
global.GovDiv: 42 -> 2100

$ ./brain-config.py /dev/ttyUSB0 --read setup1.TailGainA
setup1.TailGainA: 32767

$ ./brain-config.py /dev/ttyUSB0 --read-all
global.Version: 1
[...]
setup3.Info11: 0


WARNING: This is a very early prototype by some crazy individual on the
internet. There's obviously no guarantee it won't do horrible things to either
the FBL unit itself or anything unfortunate enough to be attached to it (like a
helicopter, for example). Use it at your own risk.

I also have nothing to do with MSH, so they obviously have even less blame if
anything bad happens.