Bug 104986 Backgound image uses an absolute path
Currently Chart uses an absolute path to indicate a backgournd image, that may cause the design unusable on other environments. Expected the background image can be definded in multiple ways like in report designer. e.g. URI(absolute path), File(relative path), Embedded Image(Encoded Image Data).
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/model/attribute/impl/AttributeFactoryImpl.java
public ActionValue createActionValue( )
	{
		ActionValueImpl actionValue = new ActionValueImpl( );
		return actionValue;
	}
	/**
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 */
	public Angle3D createAngle3D( )
	{
		Angle3DImpl angle3D = new Angle3DImpl( );
		return angle3D;
	}
	/**
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @generated
	 */
	public AxisOrigin createAxisOrigin( )
	{
		AxisOriginImpl axisOrigin = new AxisOriginImpl( );
		return axisOrigin;
	}
	/**
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @generated
	 */
	public Bounds createBounds( )
	{