README.md: use correct coverage badge
README.md: use correct coverage badge
iksaif/biggraphite,iksaif/biggraphite,Thib17/biggraphite,Thib17/biggraphite,criteo/biggraphite,criteo/biggraphite,criteo/biggraphite,criteo/biggraphite,Thib17/biggraphite,dpanth3r/biggraphite,natbraun/biggraphite,iksaif/biggraphite,iksaif/biggraphite,Thib17/biggraphite