Add the multi labels metric for the nodes and edges level
(not for segments)
	new file:   Tests/multiLab0
	new file:   Tests/multiLab0a
	new file:   Tests/multiLab1
	new file:   Tests/multiLab1a
	new file:   Tests/multiLab2
	new file:   Tests/multiLab2a
	modified:   lg.py
	modified:   testlg.py