minor formatting fix- add , in list of multiple disc-to links

_includes/discussion_links.html

@@ -1,4 +1,4 @@
 {% assign links=include.links|split:"," %}
 {% for link in links %}
-<a href="{{ link | strip | uri_escape }}">{{ link | strip | xml_escape }}</a>
+    <a href="{{ link | strip | uri_escape }}">{{ link | strip | xml_escape }}</a>{% if forloop.last == false %}, {% endif %}
 {% endfor %}