v0.10.2-with-update-6-read-support

Changes to the original v0.10.2 release:

• added new headers
• support sublevel savefile structure from update 6
• parse sets of StructProperty (only parsed in property "mRemovalLocations" of "/Script/FactoryGame.FGFoliageRemoval" for now)
• raise exception if older savefile versions are loaded or if the user tries to save the savefile (not implemented in this "fork")