Bug 185280 Expression Builder: category options rearrangement.
In expression builder under category, Available Column Bindings and Available Data sets should be listed together. Right now 'Available Column Bindings' is the first option and 'Available Data sets' is the last.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/BindingExpressionProvider.java
package org.eclipse.birt.report.designer.ui.dialogs;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import org.eclipse.birt.report.designer.internal.ui.util.DataUtil;
import org.eclipse.birt.report.designer.internal.ui.util.ExceptionHandler;
import org.eclipse.birt.report.designer.nls.Messages;
import org.eclipse.birt.report.designer.util.DEUtil;
import org.eclipse.birt.report.model.api.DataSetHandle;
import org.eclipse.birt.report.model.api.DataSetParameterHandle;
import org.eclipse.birt.report.model.api.DesignElementHandle;
import org.eclipse.birt.report.model.api.GroupHandle;
import org.eclipse.birt.report.model.api.PropertyHandle;
import org.eclipse.birt.report.model.api.ReportItemHandle;
import org.eclipse.birt.report.model.api.ResultSetColumnHandle;
import org.eclipse.birt.report.model.api.activity.SemanticException;
/**
 * 
 */
public class BindingExpressionProvider extends ExpressionProvider
{
	public static final String DATASETS = Messages.getString( "ExpressionProvider.Category.DataSets" ); 
	private DataSetHandle dataSetHandle = null;
	public BindingExpressionProvider( DesignElementHandle handle )
	{
		super( handle );
		if ( handle instanceof ReportItemHandle )
		{
			dataSetHandle = DEUtil.getFirstDataSet( handle );