Node classes for building the scenegraph

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	Interface	Description
	IDisplayable	The IDisplayable interface should be implemented by all visible objects.

	Class	Description
	ATransformable	ABSTRACT CLASS - super class for all movable objects in the object tree.
	Camera3D	The Camera3D class is used to create a camera for the Sandy world.
	Geometry3D	The Geometry3D class holds a complete description of the geometry of a Shape3D.
	Group	The Group class is used for branch nodes in the Sandy object tree.
	Node	ABSTRACT CLASS - Base class for all nodes in the object tree.
	Shape3D	The Shape3D class is the base class of all true 3D shapes.
	Sprite2D	The Sprite2D class is use to create a 2D sprite.
	Sprite3D	The Sprite3D class is use to create a 3D sprite.
	TransformGroup	The TransformGroup class is used to create transform group.