cmd/go: update go vet documentation

R=rsc, minux.ma, r
CC=golang-dev
https://golang.org/cl/10110043

src/cmd/go/doc.go

@@ -465,7 +465,7 @@ Usage:
 
 Vet runs the Go vet command on the packages named by the import paths.
 
-For more about vet, see 'godoc vet'.
+For more about vet, see 'godoc code.google.com/p/go.tools/cmd/vet'.
 For more about specifying packages, see 'go help packages'.
 
 To run the vet tool with specific options, run 'go tool vet'.

src/cmd/go/vet.go

@@ -15,7 +15,7 @@ var cmdVet = &Command{
 	Long: `
 Vet runs the Go vet command on the packages named by the import paths.
 
-For more about vet, see 'godoc vet'.
+For more about vet, see 'godoc code.google.com/p/go.tools/cmd/vet'.
 For more about specifying packages, see 'go help packages'.
 
 To run the vet tool with specific options, run 'go tool vet'.