move metrics to top of README
move metrics to top of README

Former-commit-id: 79d2244167b8e186d7ad7b3f0bb8b101d4275fc3
cboursnell/transrate,roryk/transrate,cboursnell/transrate,Blahah/transrate,cboursnell/transrate,Blahah/transrate,roryk/transrate,roryk/transrate,Blahah/transrate