Bug 119331 Library - name space terminology and behavior
During BIRT 2.0 library feature review meeting the following change was decided. - Change the term namespace to 'prefix' - By default use the library name as the prefix ( namespace ); the dialog to input prefix should be prompted only if hte auto generated prefix is not unique.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dnd/InsertInLayoutUtil.java
*            insert target like cell or ListBandProxy
	 * @param targetParent
	 *            target container like table or list
	 * @return to be inserted data item
	 * @throws SemanticException
	 */
	protected static DataItemHandle performInsertDataSetColumn(
			DataSetItemModel model, Object target, Object targetParent )
			throws SemanticException
	{
		
		
		
		
		DataItemHandle dataHandle = DesignElementFactory.getInstance( )
				.newDataItem( null );
		DataSetHandle dataSet = (DataSetHandle) model.getParent( );
		dataHandle.setValueExpr( DEUtil.getExpression( model ) );
		if ( targetParent instanceof ReportItemHandle )
		{
			ReportItemHandle container = (ReportItemHandle) targetParent;
			if ( !DEUtil.getDataSetList( container ).contains( dataSet ) )
			{
				if ( container.getDataSet( ) == null )
				{
					container.setDataSet( dataSet );
				}
			}
		}
		else