_includes/person: use https to request x3dom.js

_layouts/person.html

@@ -2,8 +2,8 @@
 layout: text
 ---
 
-<script src="http://www.x3dom.org/release/x3dom.js"></script>
-<link rel="stylesheet" href="http://www.x3dom.org/release/x3dom.css">
+<script src="https://www.x3dom.org/release/x3dom.js"></script>
+<link rel="stylesheet" href="https://www.x3dom.org/release/x3dom.css">
 
 {% capture name %}{{page.titlePrefix}} {{page.firstNames}} {{page.lastName}}{{page.titleSuffix}}{% endcapture %}
 <h1>{{ name }}</h1>