adjust feed url

Author: railsagainstignorance

feed.xml

@@ -6,7 +6,7 @@ layout: null
   <channel>
     <title>{{ site.title | xml_escape }}</title>
     <description>{{ site.description | xml_escape }}</description>
-    <link>{{ site.url }}</link>
+    <link>{{ site.github.url }}</link>
     {% for post in site.posts %}
       {% unless post.draft %}
         {% if post.layout == 'crossword-pdf' %}