We have decided that hardcoded initialization of instruments and systems is
bad. So we remove them.
Hardcoded initialization is bad because it can't be overridden from config
files or from the command line. We prefer to do it through config files that
should be, eventually, aircraft specific (*-set.xml), not global
(preferences.xml).
I've made an encoder and a transponder. The transponder gets C-Mode altitude
information from the encoder. These two might not be very usefull right now,
but I think they might come in handy when the ATC network gets going.