Minor changes to tutorial
Minor changes to tutorial

ktaneishi/deepchem,Agent007/deepchem,lilleswing/deepchem,lilleswing/deepchem,miaecle/deepchem,lilleswing/deepchem,deepchem/deepchem,miaecle/deepchem,peastman/deepchem,Agent007/deepchem,ktaneishi/deepchem,deepchem/deepchem,Agent007/deepchem,ktaneishi/deepchem,peastman/deepchem,miaecle/deepchem