Document the "random" module.

doc/site/modules/core/index.markdown

@@ -1,4 +1,4 @@
-^title Core Module
+^title Module "core"
 
 Because Wren is designed for [embedding in applications][embedding], its core
 module is minimal and is focused on working with objects within Wren. For

doc/site/modules/core/template.html

@@ -22,7 +22,7 @@
   <nav class="big">
     <ul>
       <li><a href="../">Modules</a></li>
-      <li><a href="./">Core</a></li>
+      <li><a href="./">core</a></li>
     </ul>
     <section>
       <h2>core classes</h2>
@@ -47,7 +47,7 @@
     <table>
       <tr>
         <td><a href="../">Modules</a></td>
-        <td><a href="./">Core</a></td>
+        <td><a href="./">core</a></td>
       </tr>
       <tr>
         <td colspan="2"><h2>core classes</h2></td>