Add random test to preface page in book template

templates/book.jinja

@@ -58,6 +58,15 @@
       This EPUB is a generated compilation of logs with annotations that provide context to the situatedness of this
       technology. With one book a day, a diary of chopchop is kept, stored and shared.
     </p>
+    <p> This is a random number: {{ range(1, 51) | random }}?</p>
+    {% set dice = range(1, 4) | random %}
+    {% if dice < 2 %}
+	<mark>dice = 1</mark>
+    {% elif dice < 3%}
+	<mark>dive = 2></mark>
+    {% else %}
+    	<mark>dice = 3</mark>
+    {% endif %}
   </article>
 
   <article>