Added two new properties:
/environment/temperature-sea-level-degc
/environment/pressure-sea-level-inhg
These are now supported in FGEnvironment as well, though they always
have the same value for now. They need to be hooked up to the FDMs.
/sim/freeze/master (implimented)
/sim/freeze/fuel (implimented)
/sim/freeze/position (not implimented)
/sim/freeze/time-of-day (not implimented)
/sim/freeze/master is bound to the 'p' key via keyboard.xml, however,
/sim/freeze/fuel is not bound to anything at the moment so you must
change it via the external property interface, or specify an initial
value on the command line.
restoreInitialState methods to FGGlobals, as well as the two-stage
commit described above for loading saved files. fgInit now takes a
snapshot of the initial state before handing off to the main loop, and
the GUI reInit function restores that state explicitly before calling
fgReInit.
The FlightGear patches also modify fg_props.hxx to add optional
useDefault arguments to all of the fgTie functions -- that lets you
choose whether you want to pick up any default value in the property
tree when you tie the property (the default is true).
