escape xml in example code blocks

Author: michaelbabyn

_includes/auto_examples.html

@@ -12,7 +12,7 @@ <h4 id="{{ example.name | replace:' ','-' | remove:',' | downcase | strip_html }
           {% endif %}
           {% if example.content != "" %}
             <div class="z-depth-1">
-              <pre><code class="{{page.language}}">{{ example.content }}</code></pre>
+              <pre><code class="{{page.language}}">{{ example.content | xml_escape }}</code></pre>
             </div>
           {% endif %}
           {% if example.description %}