Add a “build <hash> on <date>” footer

Author: ChrisCummins

Gemfile

@@ -1,3 +1,4 @@
 source 'https://rubygems.org'
 gem 'github-pages', group: :jekyll_plugins
 gem 'jekyll-redirect-from'
+gem 'jekyll-github-metadata'

_config.yml

@@ -83,6 +83,7 @@ kramdown:
 # Extensions
 plugins:
   - jekyll-redirect-from  # enable "refirect_from" in front matter
+  - jekyll-github-metadata  # add 'site.github' github metadata
 
 sass:
   style: compressed

_layouts/default.html

@@ -111,7 +111,8 @@ <h1>
         <div id="footer" class="col-sm-9 noselect">
           <hr/>
           <p id="copyright">
-            &copy; {{ site.copyright.owner }} {{ site.copyright.year }}
+            &copy; {{ site.copyright.owner }} {{ site.copyright.year }}<br/>
+            build <a href="{{ site.github.repository_url }}/commit/{{ site.github.build_revision }}" title>{{ site.github.build_revision | truncate: 8, "" }}</a> on {{ site.time | date: '%Y-%m-%d' }}
           </p>
         </div> <!-- /#footer -->
       </div> <!-- /.row -->

css/styles.scss

@@ -483,6 +483,11 @@ a.decorated {
         font-size: 13px;
         font-weight: 300;
         color: $color-subtle;
+
+        // No color highlight for the "build <hash>" link in the footer.
+        a {
+            color: $color-subtle;
+        }
     }
 }