RF: integer division in making lattice grid
RF: integer division in making lattice grid

Use integer division explicitly for making lattice grid (fixes Python 3
test failure).

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