TEST: added tests for sumsqdiff module
TEST: added tests for sumsqdiff module

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