markdownify browser bugs, add config vars for shorthand urls

docs/_layouts/default.html

@@ -31,6 +31,9 @@
         {% elsif page.url contains "examples" %}
           <h1>About</h1>
           <p class="lead">Learn about the project's history, meet the maintaining teams, and find out how to use the Bootstrap brand.</p>
+        {% elsif page.url contains "browser-bugs" %}
+          <h1>Browser bugs</h1>
+          <p class="lead">A list of the browser bugs that Bootstrap is currently grappling with.</p>
         {% endif %}
 
         {% include ads.html %}