✨ feat: add date visibility options to post list (#330)

Co-authored-by: welpo <welpo@users.noreply.github.com>

templates/atom.xml

@@ -9,6 +9,9 @@
 <?xml-stylesheet href="{{ get_url(path='/feed_style.xsl', trailing_slash=false) | safe }}" type="text/xsl"?>
 <feed xmlns="http://www.w3.org/2005/Atom" xmlns:base="http://purl.org/atompub/base/1.0/" xml:lang="{{ lang }}" xml:base="{{ config.base_url }}">
     <str:translations xmlns:str="https://github.com/welpo/tabi">
+        <str:separator>
+            {{  config.extra.separator | default(value="•") }}
+        </str:separator>
         <str:about_feeds>
             {{- macros_translate::translate(key="about_feeds", default="This is a web feed, also known as an Atom feed. Subscribe by copying the URL from the address bar into your newsreader", language_strings=language_strings) -}}
         </str:about_feeds>
@@ -18,6 +21,9 @@
         <str:recent_posts>
             {{- macros_translate::translate(key="recent_posts", default="Recent posts", language_strings=language_strings) -}}
         </str:recent_posts>
+        <str:last_updated_on>
+            {{- macros_translate::translate(key="last_updated_on", default="Updated on $DATE", language_strings=language_strings) -}}
+        </str:last_updated_on>
     </str:translations>
 
     {#- Load extra CSS (skin) if set in config.toml -#}
@@ -34,6 +40,7 @@
         <subtitle>{{ config.description }}</subtitle>
     {%- endif %}
     <link href="{{ feed_url | safe }}" rel="self" type="application/atom+xml"/>
+    <post_listing_date>{{ config.extra.post_listing_date | default(value="date") }}</post_listing_date>
     <link href="
         {%- if section -%}
             {{ section.permalink | escape_xml | safe }}