fix missing super.sync
makes nframes optional in split()

Conflicts:
	h2d/Tile.hx
fixed Sprite.getBounds when relativeTo has rotation

Conflicts:
	h2d/Sprite.hx
	samples/bounds/Bounds.hx
prevent getBounds() with a different scene (not supported) + fix some issues when getScene is null
fixed getBounds when not on scene (use new Sprite instead of top parent)
merge back Nico's bounds ( seems to work very well )