FlightGear - Flight Simulator FGAddon

777: Enable revision 52 (20200522) by Lars0817: correct Thrust reverser messages on Eicas.

Beechcraft C18 S: Bumpmap added, file reorganization, float version added, compatibility with Compositor

Beechcraft C18 S: Bumpmap added, file reorganization, float version added, compatibility with Compositor

Beechcraft Model 17 Staggerwing: Revision of the FDM. Reorganization of the files. Added bumpmaps. Compatibility with Compositor

Beechcraft Model 17 Staggerwing: Revision of the FDM. Reorganization of the files. Added bumpmaps. Compatibility with Compositor

Bleriot XI: Revision of the FDM. Reorganization of the files. Compositor Compatibility

Update to match refactored C++ implementation.

PA28: Adjust /instrumentation/gps/over-flight-distance-nm according to forum discussion https://forum.flightgear.org/viewtopic.php?f=25&t=38292#p376456

A320: Merge trunk to release/2020.3

A320: Remove files that were meant to be deleted (rename or replacement). Through user error, they were committed again to fgaddon rather than be deleted.