Bug 188578 Add "displayColumnName" on TabularLevel
Add Property "displayColumnName" on TabbularLevel and corresponding APIs on handle. Property Type: expression.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/writer/ModuleWriter.java
*/
	protected XMLWriter writer = null;
	/**
	 * The base 64 codec for embedded images.
	 */
	protected static Base64 base = new Base64( );
	/**
	 * The compatibility to create bound columns.
	 */
	protected BoundColumnsWriterMgr boundColumnsMgr = null;
	/**
	 * Control flag indicating whether need mark line number.
	 */
	protected boolean markLineNumber = true;
	/**
	 * Returns the module to write.
	 * 
	 * @return the module to write
	 */
	abstract protected Module getModule( );
	/**
	 * Writes the report design to a file.
	 * 
	 * @param outputFile
	 *            output file into which to write the design
	 * 
	 * @throws IOException
	 *             if a write error occurs
	 */
	public void write( File outputFile ) throws IOException