.hgtags: Tag release.r58.

TBR=adg
CC=golang-dev
http://codereview.appspot.com/4631083

.hgtags

@@ -6,4 +6,5 @@ f3ef978cda6fabc10f6039aeed960340547c6d5a release.r56
 097a1c90eb4bf73ecacbcef71c09298f4a596dcd weekly
 fa1080cfc0a4d0fa24844bc50124aed892365059 release.r57.1
 fa1080cfc0a4d0fa24844bc50124aed892365059 release.r57.2
-fa1080cfc0a4d0fa24844bc50124aed892365059 release
+cfe37a63cede6cd072434965e6ea426b90bcb223 release.r58
+cfe37a63cede6cd072434965e6ea426b90bcb223 release