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
writeContents( obj, ITemplateParameterDefinitionModel.DEFAULT_SLOT,
				DesignSchemaConstants.DEFAULT_TAG );
		writer.endElement( );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.elements.ElementVisitor#visitTemplateReportItem(org.eclipse.birt.report.model.elements.TemplateReportItem)
	 */
	public void visitTemplateReportItem( TemplateReportItem obj )
	{
		
		boundColumnsMgr.dealTemplateReportItem( obj, getModule( ) );
		writer.startElement( DesignSchemaConstants.TEMPLATE_REPORT_ITEM_TAG );
		super.visitTemplateReportItem( obj );
		writeStructureList( obj, TemplateReportItem.VISIBILITY_PROP );
		writeUserPropertyDefns( obj );
		writeUserPropertyValues( obj );
		writer.endElement( );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.elements.ElementVisitor#visitStyle(org.eclipse.birt.report.model.elements.Style)
	 */
	public void visitStyle( Style obj )
	{
		writer.startElement( DesignSchemaConstants.STYLE_TAG );
		super.visitStyle( obj );
		writeStyleProps( obj );