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
measureColumnName[0] = "measure1";
		Cube cube = new Cube( cubeName, documentManager );
		cube.create( getKeyColNames(dimensions), dimensions, factTable2, measureColumnName, new StopSign( ) );
		
		cube.close( );
		documentManager.flush( );
	}
	
	/**
	 * 
	 * @param dimensions
	 * @return
	 */
	private static String[][] getKeyColNames( IDimension[] dimensions )
	{
		String[][] keyColumnName = new String[dimensions.length][];
		for ( int i = 0; i < dimensions.length; i++ )
		{
			ILevel[] levels = dimensions[i].getHierarchy( ).getLevels( );
			ILevel detailLevel = levels[levels.length-1];
			keyColumnName[i] = detailLevel.getKeyNames( );
		}
		return keyColumnName;
	}
	private String[] distinct( String[] values )
	{
		String[] lValues = new String[values.length];
		System.arraycopy( values, 0, lValues, 0, values.length );
		Arrays.sort( lValues );
		List tempList = new ArrayList( );