[release-branch.go1.4] doc: scrub references to code.google.com

These are the references that affect current Go users.
I left intact references in older release notes;
we can figure out what to do with them later.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/186140043

Conflicts:
	doc/go1.4.html

Change-Id: I1032686f2b3ac6dacaf8f114b8c35cdf221330ca
diff --git a/doc/help.html b/doc/help.html
index a307b2a..2cc4780 100644
--- a/doc/help.html
+++ b/doc/help.html
@@ -24,7 +24,7 @@
 <p>
 Search the <a href="//groups.google.com/group/golang-nuts">golang-nuts</a>
 archives and consult the <a href="/doc/go_faq.html">FAQ</a> and
-<a href="//code.google.com/p/go-wiki/wiki">wiki</a> before posting.
+<a href="//golang.org/wiki">wiki</a> before posting.
 </p>
 
 <h3 id="irc"><a href="irc:irc.freenode.net/go-nuts">Go IRC Channel</a></h3>