tour: add link to Bahasa Indonesia translation.

Change-Id: I6082947d86850b97fa04e076e917ff6524abfbf8
Reviewed-on: https://go-review.googlesource.com/15017
Reviewed-by: Andrew Gerrand <adg@golang.org>
diff --git a/content/welcome.article b/content/welcome.article
index dc6aa84..c0c5f45 100644
--- a/content/welcome.article
+++ b/content/welcome.article
@@ -52,6 +52,7 @@
 - [[http://go-tour-de.appspot.com/][German — Deutsch]]
 - [[http://go-tour-es.appspot.com/][Spanish — Español]]
 - [[http://go-tour-fr.appspot.com/][French — Français]]
+- [[http://go-tour-id2.appspot.com/][Indonesia — Bahasa]]
 - [[http://go-tour-ita.appspot.com/][Italian — Italiano]]
 - [[http://go-tour-he.appspot.com/][Hebrew — עִבְרִית]]
 - [[http://go-tour-jp.appspot.com/][Japanese — 日本語]]