Add EOL versions back to the sitemap (#165)

Author: AA-Turner

templates/robots.txt

@@ -16,3 +16,10 @@ Disallow: /2.5/
 Disallow: /2.6/
 Disallow: /2.7/
 Disallow: /3.0/
+Disallow: /3.1/
+Disallow: /3.2/
+Disallow: /3.3/
+Disallow: /3.4/
+Disallow: /3.5/
+Disallow: /3.6/
+Disallow: /3.7/