Add Atom feed using the jekyll-feed plugin (#2646)

Author: ptgolden

_config.yml

@@ -10,6 +10,9 @@ author:
   name: OBO Technical WG
 plugins:
   - jekyll-sitemap
+  - jekyll-feed
+feed:
+  disable_in_development: true
 ## --Anything above this line can be edited in _config_header.yml --
 ## --Everything below this line automatically generated in _config.yml --
 ontologies:

_config_header.yml

@@ -10,5 +10,8 @@ author:
   name: OBO Technical WG
 plugins:
   - jekyll-sitemap
+  - jekyll-feed
+feed:
+  disable_in_development: true
 ## --Anything above this line can be edited in _config_header.yml --
 ## --Everything below this line automatically generated in _config.yml --

_includes/head.html

@@ -14,6 +14,8 @@
 <!-- Custom stylesheet -->
 <link rel="stylesheet" href="/assets/css/style.css">
 
+{% feed_meta %}
+
 <style>
 html, body {
     height: 100%;