Bug 117149 Add additional datapoint markers
I would like to propose adding additional datapoint markers. Attached is a set of markers I would like supported.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/model/attribute/MarkerType.java
/**
	 * The '<em><b>Circle</b></em>' literal value.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @see #CIRCLE_LITERAL
	 * @model name="Circle"
	 * @generated
	 * @ordered
	 */
	public static final int CIRCLE = 3;
	/**
	 * The '<em><b>Icon</b></em>' literal value.
	 * <!-- begin-user-doc -->
	 * <p>
	 * If the meaning of '<em><b>Icon</b></em>' literal object isn't clear,
	 * there really should be more of a description here...
	 * </p>
	 * <!-- end-user-doc -->
	 * @see #ICON_LITERAL
	 * @model name="Icon"
	 * @generated
	 * @ordered
	 */
	public static final int ICON = 4;
	/**
	 * The '<em><b>Crosshair</b></em>' literal object.
	 * <!-- begin-user-doc
	 * -->
	 * <p>
	 * If the meaning of '<em><b>Crosshair</b></em>' literal object isn't