Merge pull request #3142 from Calinou/robots-txt-disallow-3.2

Prevent the `3.2` branch from being indexed by search engines

robots.txt

@@ -1,4 +1,5 @@
 user-agent: *
+disallow: /*/3.2
 disallow: /*/3.1
 disallow: /*/3.0
 disallow: /*/2.0