RF - Updated docstrings of Tensor class in dti.py
RF - Updated docstrings of Tensor class in dti.py

Messaoud-Boudjada/dipy,beni55/dipy,FrancoisRheaultUS/dipy,samuelstjean/dipy,Messaoud-Boudjada/dipy,FrancoisRheaultUS/dipy,villalonreina/dipy,sinkpoint/dipy,jyeatman/dipy,matthieudumont/dipy,nilgoyyou/dipy,demianw/dipy,rfdougherty/dipy,samuelstjean/dipy,maurozucchelli/dipy,StongeEtienne/dipy,oesteban/dipy,mdesco/dipy,jyeatman/dipy,samuelstjean/dipy,mdesco/dipy,nilgoyyou/dipy,matthieudumont/dipy,beni55/dipy,oesteban/dipy,JohnGriffiths/dipy,maurozucchelli/dipy,demianw/dipy,rfdougherty/dipy,villalonreina/dipy,sinkpoint/dipy,maurozucchelli/dipy,StongeEtienne/dipy,JohnGriffiths/dipy