Bug 183918 get relative file path of linkage library
model/org.eclipse.birt.report.model.tests/test/org/eclipse/birt/report/model/library/DesignLoadLibraryTest.java
assertEquals( "Lib.base", childLabel.getExtends( ).getQualifiedName( ) ); 		
		NameSpace ns = ( (Module) includeLib.getElement( ) )
				.getNameSpace( Module.ELEMENT_NAME_SPACE );
		ns
				.rename(
						includeLib.findElement( "base" ).getElement( ), "base", "newBase" ); 
		includeLib.findElement( "newBase" ).getElement( ).setName( "newBase" ); 
		childLabel = null;
		childLabel = (LabelHandle) designHandle.getElementFactory( )
				.newElementFrom( baseLabel, "childTwo" ); 
		designHandle.getBody( ).add( childLabel );
		save( );
		compareFile( "LibraryWithLocation_golden.xml" );