Bug 117149 Add additional datapoint markers
I would like to propose adding additional datapoint markers. Attached is a set of markers I would like supported.
chart/org.eclipse.birt.chart.ui.extension/src/org/eclipse/birt/chart/ui/swt/series/LineSeriesAttributeComposite.java
gd.horizontalIndent = 5;
			btnPalette.setLayoutData( gd );
			gd = new GridData( );
			gd.horizontalSpan = 2;
			gd.horizontalIndent = 5;
			btnCurve.setLayoutData( gd );
		}
		
		GridLayout glMarker = new GridLayout( );
		glMarker.numColumns = 2;
		glMarker.marginHeight = 4;
		glMarker.marginWidth = 4;
		glMarker.verticalSpacing = 4;
		glMarker.horizontalSpacing = 4;
		grpMarker = new Group( this, SWT.NONE );
		GridData gdGRPMarker = new GridData( GridData.FILL_BOTH );
		gdGRPMarker.horizontalSpan = 2;
		grpMarker.setLayoutData( gdGRPMarker );
		grpMarker.setLayout( glMarker );
		grpMarker.setText( Messages.getString( "LineSeriesAttributeComposite.Lbl.Marker" ) ); 
		btnMarkerVisible = new Button( grpMarker, SWT.CHECK );
		GridData gdBTNVisible = new GridData( );
		gdBTNVisible.horizontalSpan = 2;
		btnMarkerVisible.setLayoutData( gdBTNVisible );
		btnMarkerVisible.setText( Messages.getString( "LineSeriesAttributeComposite.Lbl.IsVisible" ) ); 
		btnMarkerVisible.addSelectionListener( this );
		btnMarkerVisible.setSelection( ( (LineSeries) series ).getMarker( )
				.isVisible( ) );
		Label lblType = new Label( grpMarker, SWT.NONE );
		GridData gdLBLType = new GridData( );