added category tag to RSS entry

feed.xml

@@ -29,6 +29,7 @@ layout: none
     <uri>{{ site.url }}</uri>
     <email>{{ site.owner.email }}</email>
   </author>
+  {% for tag in post.tags %}<category scheme="{{ site.url }}/tags/#{{ tag | cgi_encode }}" term="{{ tag }}" />{% endfor %}
   <content type="html">{{ post.content | xml_escape }}
   &lt;p&gt;&lt;a href=&quot;{{ site.url }}{{ post.url }}&quot;&gt;{{ post.title }}&lt;/a&gt; was originally published by {{ site.owner.name }} at &lt;a href=&quot;{{ site.url }}&quot;&gt;{{ site.title }}&lt;/a&gt; on {{ post.date | date: "%B %d, %Y" }}.&lt;/p&gt;</content>
 </entry>