justinsb: nodeup download should try all mirrors

JobBuild
2462ab1c
08-22 05:06
e0b00fb8
08-22 04:21
pull-kops-bazel-build 1164403322652725252 1164392125467463681
pull-kops-bazel-test 1164403322652725253 1164392125480046592
pull-kops-e2e-kubernetes-aws 1164403322648530949 1164392125463269376
pull-kops-verify-bazel 1164403322652725254 1164392125475852288
pull-kops-verify-boilerplate 1164403322652725248 1164392125480046593
pull-kops-verify-gofmt 1164403322652725249 1164392125475852289
pull-kops-verify-govet 1164403322652725250 1164392125471657984
pull-kops-verify-packages 1164403322652725251 1164392125467463680