-Fixed pathfinder running into lava & water when it shouldn't.
FlyPathFinder:
-Simplified nodeTypeToOffset switch statement, removed unused function, and made air always return an open path node type.
EntityNPCInterface:
-Fixed "In Air" drowning type. Breathes underwater now.
EntityNPCFlying:
-Fixed NPCs still using flight movement when not being able to breathe.
ICustomNpc:
-Added canBreathe() function