DOC - minor edits to docstrings
DOC - minor edits to docstrings

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