Implement baseLine for node distance Analysis.
Solve question 3)
Delete function nodeDistance().
Add function findSmallestDistaneAuthor(G)
Solve question 4)
The author who has the smallest average distance is  Chen
The distance is  1.7935828877005346
Remove the comment before: degreeAnalysis, componentAnalysis,
nodeDistanceAnalysis.
Correct the error calculating average path length.
Change sum(lengthList)/len(lengthList)-1
to     sum(lengthList)/(len(lengthList)-1)
Merge branch 'NodeDistanceAnalysis'

Conflicts:
	CoauthorShip/src/Test.py