Bug 184762 BIRT Model - Enhancments to the level defintion
xtab/org.eclipse.birt.report.item.crosstab.core/src/org/eclipse/birt/report/item/crosstab/core/de/LevelViewHandle.java
* the validation of the whole crosstab.
	 * 
	 * @param measureList
	 * @param functionList
	 * @return
	 * @throws SemanticException
	 */
	public CrosstabCellHandle addSubTotal( List measureList, List functionList )
			throws SemanticException
	{
		return new LevelViewTask( this ).addSubTotal( measureList, functionList );
	}
	/**
	 * Removes the aggregation header cell if it is not empty, otherwise do
	 * nothing. This method will remove the aggregation header cell in this
	 * level and adjust the measure aggregations to ensure the validation of the
	 * whole crosstab.
	 */
	public void removeSubTotal( ) throws SemanticException
	{
		new LevelViewTask( this ).removeSubTotal( );
	}
	/**
	 * Removes the aggregation header cell if it is not empty on particular
	 * measure, otherwise do nothing. This method will remove the aggregation
	 * header cell in this level and adjust the measure aggregations to ensure
	 * the validation of the whole crosstab.
	 */
	public void removeSubTotal( int measureIndex ) throws SemanticException
	{