Bug 136279 Structure and table datatypes should be hidden.
Description: Structure and table datatype should be hidden. Steps to reproduce: In table data binding, I saw structure and table two datatypes. They are not supported now, so they should be removed.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/writer/DesignWriter.java
{
	/**
	 * The design context used to convert units.
	 */
	private ReportDesign design;
	/**
	 * Constructs a writer with the specified design.
	 * 
	 * @param design
	 *            the internal representation of the design
	 */
	public DesignWriter( ReportDesign design )
	{
		this.design = design;
	}
	/**
	 * Write the top-level Report tag, and the properties and contents of the
	 * report itself.
	 * 
	 * @param obj
	 *            the object to write
	 */
	public void visitReportDesign( ReportDesign obj )
	{
		writer.startElement( DesignSchemaConstants.REPORT_TAG );
		super.visitReportDesign( obj );