re-add rss feeds

app/templates/base.atom

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<feed xmlns="http://www.w3.org/2005/Atom">
+  {%- if self.title() -%}
+  <title>{%- block title -%}{%- endblock -%}</title>
+  {%- else -%}
+  <title>{{- config.SITE_NAME -}}</title>
+  {%- endif -%}
+  {%- if self.feed_updated() -%}
+  <updated>{%- block feed_updated -%}{%- endblock -%}</updated>
+  {%- else -%}
+  <updated>{{- get_time_now() | iso8601 -}}</updated>
+  {%- endif -%}
+  <id>{{- __current_page -}}</id>
+  <link rel="self" href="{{ __current_page }}" />
+  <link href="{%- block canonical_link -%}{%- endblock -%}" />
+  {%- if self.feed_author() -%}
+    <author>{%- block feed_author -%}{%- endblock -%}</author>
+    {%- endif -%}
+    {%- block content -%}{%- endblock -%}
+</feed>