add rss feed

theme_customization/main.html

+{% extends "base.html" %}
+
+{% block extrahead %}
+  <!-- RSS Feed -->
+  <link rel="alternate" type="application/rss+xml" title="RSS feed of created content" href="{{ config.site_url }}feed_rss_created.xml">
+  <link rel="alternate" type="application/rss+xml" title="RSS feed of updated content" href="{{ config.site_url }}feed_rss_updated.xml">
+{% endblock %}
\ No newline at end of file