fix typo/oversight: s/Title/ToTitle/. the comment was already correct

R=rsc
DELTA=1  (0 added, 0 deleted, 1 changed)
OCL=35964
CL=35979

src/pkg/bytes/bytes.go

@@ -240,7 +240,7 @@ func ToLower(s []byte) []byte {
 }
 
 // ToTitle returns a copy of the byte array s with all Unicode letters mapped to their title case.
-func Title(s []byte) []byte {
+func ToTitle(s []byte) []byte {
 	return Map(unicode.ToTitle, s);
 }