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/src/org/eclipse/birt/data/engine/olap/driver/DimensionAxis.java
/**
	 * 
	 * @return
	 */
	public int getLevelIndex( )
	{
		return this.levelIndex;
	}
	
	/**
	 * 
	 * @return
	 */
	public int getDimensionAxisIndex( )
	{
		return this.dimAxisIndex;
	}
	/**
	 * 
	 * @return
	 */
	public int getAttributeName( )
	{
		return this.attrIndex;
	}
	
	/**
	 * 
	 * @return
	 */