Move the documentation from race.go to doc.go, because
race.go uses +build race, so it's not normally parsed by go doc.
Rephrase the documentation for end users, provide link to race
detector manual.
Fixes #5444.
R=golang-dev, minux.ma, adg, r
CC=golang-dev
https://golang.org/cl/
9144050
--- /dev/null
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package race implements data race detection logic.
+// No public interface is provided.
+// For details about the race detector see
+// http://golang.org/doc/articles/race_detector.html
+package race
// +build race,linux,amd64 race,darwin,amd64 race,windows,amd64
-// Package race provides low-level facilities for data race detection.
package race
/*