Bug 182895 Support sort on Level attribute.
Currently in OLAP engine we only support sort on level key value. We should go ahead to support sort on level attribute value.
data/org.eclipse.birt.data.tests/test/org/eclipse/birt/data/engine/olap/api/CubeFeaturesTest.java
CubeFilterDefinition filter3 = new CubeFilterDefinition( new ScriptExpression( "data[\"country_year_total\"] < 300"));
		
		filter3.setAxisQualifierLevels( new ILevelDefinition[]{level21} );
		filter3.setAxisQualifierValues( new Object[]{"2002"} );
		filter3.setTargetLevel( level11 );
		
		CubeSortDefinition sorter4 = new CubeSortDefinition();
		sorter4.setExpression( "dimension[\"dimension1\"][\"level13\"]" );
		sorter4.setAxisQualifierLevels( null );
		sorter4.setAxisQualifierValues( null );
		sorter4.setTargetLevel( level13 );
		sorter4.setSortDirection( ISortDefinition.SORT_DESC );
		
		
		CubeSortDefinition sorter5 = new CubeSortDefinition();
		sorter5.setExpression( "dimension[\"dimension1\"][\"level11\"]" );
		sorter5.setAxisQualifierLevels( null );
		sorter5.setAxisQualifierValues( null );
		sorter5.setTargetLevel( level11 );
		sorter5.setSortDirection( ISortDefinition.SORT_DESC );
		
	/*	
		SortDefinition sorter3 = new SortDefinition();
		sorter3.setExpression( "dimension[\"dimension1\"][\"level12\"]" );
		sorter3.setSortDirection( ISortDefinition.SORT_DESC );
	*/	
		cqd.addFilter( filter1 );
		cqd.addFilter( filter2 );
		cqd.addFilter( filter3 );
		cqd.addSort( sorter4 );