Bug 161429 center position missing for gantt chart
When designing a gantt chart, it should be possible to display the labels inside the bar, using a new "center" attribute. See how it should like in UI and output in attached screenshot.
chart/org.eclipse.birt.chart.ui.extension/src/org/eclipse/birt/chart/ui/swt/wizard/format/popup/series/SeriesLabelSheet.java
{
			GridLayout layout = new GridLayout( 2, false );
			layout.horizontalSpacing = 0;
			cmpTop.setLayout( layout );
			cmpTop.setLayoutData( new GridData( GridData.FILL_BOTH ) );
		}
		Composite cmpLeft = new Composite( cmpTop, SWT.NONE );
		{
			cmpLeft.setLayout( new GridLayout( ) );
			cmpLeft.setLayoutData( new GridData( GridData.FILL_BOTH ) );
		}
		Composite cmpRight = new Composite( cmpTop, SWT.NONE );
		{
			cmpRight.setLayout( new GridLayout( ) );
			cmpRight.setLayoutData( new GridData( GridData.FILL_BOTH ) );
		}
		createAttributeArea( cmpLeft );
		grpOutline = new Group( cmpLeft, SWT.NONE );
		GridData gdGOutline = new GridData( GridData.FILL_HORIZONTAL );
		gdGOutline.heightHint = 110;
		grpOutline.setLayoutData( gdGOutline );
		grpOutline.setText( Messages.getString( "LabelAttributesComposite.Lbl.Outline" ) ); 
		grpOutline.setLayout( new FillLayout( ) );
		
		liacOutline = new LineAttributesComposite( grpOutline,
				SWT.NONE,
				getContext( ),
				getSeriesForProcessing( ).getLabel( ).getOutline( ),
				true,
				true,