the static system has an optional "tau" parameter to
define the rate at which the output value changes.
Setting this value to zero now disables the filter.
This prevents wrong airspeed indications on rapid
altitude changes. No functional changes if tau has
other-than-zero values (e.g. the default systems).
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 added two new debug log types for the instrumentation and systems. They
used to use the autopilot debug log, because I couldn't figure out how to
make new log types. Well, now I have figured it out. ;-)
Instrumentation and systems are now configureable from xml files. The two
generic configurations generic-systems.xml and generic-instrumentation.xml
configures the systems and instrumentation as it was hardcoded. You can
override the generic configurations in a similar way as you override the
autopilot configuration.
