Revert "Project modernization (#630)"

This code was not tested and breaks in Release builds, reverting to restore
functionality of the nightly. All in-game menus do not work and generating
a world crashes.

This reverts commit a9be52c41a.

Minecraft.World/LeverTile.cpp

@@ -10,7 +10,7 @@ LeverTile::LeverTile(int id) : Tile(id, Material::decoration,isSolidRender())
 
 AABB *LeverTile::getAABB(Level *level, int x, int y, int z)
 {
-	return nullptr;
+	return NULL;
 }
 
 bool LeverTile::blocksLight()