Bug 213126 Add support for DataEngine-leve dataset cache
In many cases the DataEngine-leve dataset cache is useful which ensure that a dataset is executed one time during rendering one report. To support this feature a new dataset property should be added. The Birt customer can choose whether this dataset need to be cached or not by setting the property in deisgn time.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/writer/ModuleWriter.java
/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.elements.ElementVisitor#visitSortElement(org.eclipse.birt.report.model.elements.SortElement)
	 */
	public void visitSortElement( SortElement obj )
	{
		writer.startElement( DesignSchemaConstants.SORT_ELEMENT_TAG );
		markLineNumber( obj );
		super.visitSortElement( obj );
		property( obj, ISortElementModel.KEY_PROP );
		property( obj, ISortElementModel.DIRECTION_PROP );
		writeContents( obj, ISortElementModel.MEMBER_PROP );
		writer.endElement( );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.elements.ElementVisitor#visitMultiView(org.eclipse.birt.report.model.elements.MultiView)
	 */
	public void visitMultiView( MultiViews obj )
	{
		writer.startElement( DesignSchemaConstants.MULTI_VIEWS_TAG );
		markLineNumber( obj );
		super.visitMultiView( obj );
		property( obj, IMultiViewsModel.INDEX_PROP );
		writeContents( obj, IMultiViewsModel.VIEWS_PROP );
		writer.endElement( );
	}
}