bytes, os/exec, strings: fix a few BUG comments

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Change-Id: I9635de9b86f00d20ec108097fee4d4a8f76237b2
Reviewed-on: https://go-review.googlesource.com/1952Reviewed-by: Russ Cox <rsc@golang.org>

src/bytes/bytes.go

@@ -443,7 +443,7 @@ func isSeparator(r rune) bool {
 // Title returns a copy of s with all Unicode letters that begin words
 // mapped to their title case.
 //
-// BUG: The rule Title uses for word boundaries does not handle Unicode punctuation properly.
+// BUG(rsc): The rule Title uses for word boundaries does not handle Unicode punctuation properly.
 func Title(s []byte) []byte {
 	// Use a closure here to remember state.
 	// Hackish but effective. Depends on Map scanning in order and calling

src/os/exec/exec.go

@@ -80,7 +80,7 @@ type Cmd struct {
 	// new process. It does not include standard input, standard output, or
 	// standard error. If non-nil, entry i becomes file descriptor 3+i.
 	//
-	// BUG: on OS X 10.6, child processes may sometimes inherit unwanted fds.
+	// BUG(rsc): On OS X 10.6, child processes may sometimes inherit unwanted fds.
 	// http://golang.org/issue/2603
 	ExtraFiles []*os.File
 

src/strings/strings.go

@@ -520,7 +520,7 @@ func isSeparator(r rune) bool {
 // Title returns a copy of the string s with all Unicode letters that begin words
 // mapped to their title case.
 //
-// BUG: The rule Title uses for word boundaries does not handle Unicode punctuation properly.
+// BUG(rsc): The rule Title uses for word boundaries does not handle Unicode punctuation properly.
 func Title(s string) string {
 	// Use a closure here to remember state.
 	// Hackish but effective. Depends on Map scanning in order and calling