Fix scatterplot lines (need to PR this into nvd3)
Fix scatterplot lines (need to PR this into nvd3)

aaldaber/owid-grapher,OurWorldInData/owid-grapher,aaldaber/owid-grapher,mispy/our-world-in-data-grapher,mispy/our-world-in-data-grapher,aaldaber/owid-grapher,aaldaber/owid-grapher,owid/owid-grapher,OurWorldInData/our-world-in-data-grapher,owid/owid-grapher,OurWorldInData/owid-grapher,mispy/our-world-in-data-grapher,mispy/our-world-in-data-grapher,owid/owid-grapher,OurWorldInData/our-world-in-data-grapher,OurWorldInData/our-world-in-data-grapher,OurWorldInData/our-world-in-data-grapher,OurWorldInData/owid-grapher,OurWorldInData/owid-grapher,OurWorldInData/owid-grapher,owid/owid-grapher,owid/owid-grapher,aaldaber/owid-grapher,mispy/our-world-in-data-grapher