Bugs reported by Andreas Spiekermann; thanks!
* Models/B-1B.xml, Models/Instruments-3d/gear_ind.xml: consistently
use /gear/gear[0] for the front gear, /gear/gear[1] for left main
and /gear/gear[2] for right main (instead of a mixture of
/gear/gear[0..4]).
* B-1B-set.xml: add the wing sweep position properties to the replay
file.
