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
while ( memberIter.hasNext( ) )
			{
				PropertyDefn memberDefn = (PropertyDefn) memberIter.next( );
				
				
				
				writeMember( struct, memberDefn );
			}
			writer.endElement( );
		}
		writer.endElement( );
	}
	/**
	 * Writes the structure list of the give property definition for given
	 * structure.
	 * 
	 * @param obj
	 *            the structure to write
	 * @param memberName
	 *            the name of the structure list property to write
	 */
	private void writeStructureList( IStructure obj, String memberName )
	{
		PropertyDefn prop = (PropertyDefn) obj.getDefn( )
				.getMember( memberName );
		assert prop != null;
		assert prop.getTypeCode( ) == IPropertyType.STRUCT_TYPE
				&& prop.isList( );
		assert obj instanceof Structure;
		List list = (List) ( (Structure) obj ).getLocalProperty( getModule( ),