Replace various final fields in Aircraft with a reference to AircraftType
Remove defaultAircraft field in AircraftController
Remove unused isActive and aircraftName fields of AircraftType
Moved difficulty config code into GameDifficulty (which is now a class)
Remove unused Exitpoint.radius field
Fix various bugs / warnings found by intellij
Rewritten aircraft drawing in flightpath to use foreach loop
Merge branch 'master' of https://github.com/sepr-hou/ini-hou

Conflicts:
	src/main/java/seprini/controllers/AircraftController.java
Fix compile error in AircraftTest