Removed gfa calculation from csd example as gfa is not recommended for odfs as sharp as the csd ones
Removed gfa calculation from csd example as gfa is not recommended for odfs as sharp as the csd ones

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