FlightGear - Flight Simulator FGAddon

This is the 3rd patch 'flightgear-fgaddon_path_fix3_Instruments-3d.patch'
attached to the thread at
https://sourceforge.net/p/flightgear/mailman/message/33744249/ .

Due to the spinning out of the aircraft from FGData into the new FGAddon
repository, a number of aircraft now either do not work or have missing features
due to now incorrect file path assumptions. This fixes the incorrect references
to the Aircraft/Instruments-3d/ path for the aircraft bluebird,
Cessna-208-Caravan, Cessna337, fokker100, fokker50, Hawker-Siddeley-Nimrod, and
pittss1c (the affected Citation files were deleted since the post).