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/impl/MarkerImpl.java
* The default value of the '{@link #getType() <em>Type</em>}' attribute.
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @see #getType()
	 * @generated
	 * @ordered
	 */
	protected static final MarkerType TYPE_EDEFAULT = MarkerType.CROSSHAIR_LITERAL;
	/**
	 * The cached value of the '{@link #getType() <em>Type</em>}' attribute.
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @see #getType()
	 * @generated
	 * @ordered
	 */
	protected MarkerType type = TYPE_EDEFAULT;
	/**
	 * This is true if the Type attribute has been set.
	 * <!-- begin-user-doc -->
	 * <!-- end-user-doc -->
	 * @generated
	 * @ordered
	 */
	protected boolean typeESet = false;
	/**
	 * The default value of the '{@link #getSize() <em>Size</em>}' attribute.
	 * <!-- begin-user-doc --> <!-- end-user-doc -->
	 * @see #getSize()
	 * @generated
	 * @ordered
	 */