DOC: updated bundle visualization tutorial
DOC: updated bundle visualization tutorial

JohnGriffiths/dipy,villalonreina/dipy,JohnGriffiths/dipy,nilgoyyou/dipy,villalonreina/dipy,matthieudumont/dipy,nilgoyyou/dipy,StongeEtienne/dipy,StongeEtienne/dipy,matthieudumont/dipy,FrancoisRheaultUS/dipy,FrancoisRheaultUS/dipy