First attempt at a global latest changes overview.

- uses a wiki_options entry named :latest_changes_count instead of a
  constant
- lists modified pages with links

lib/gollum/templates/latest_changes.mustache

@@ -0,0 +1,39 @@
+<div id="wiki-wrapper" class="history">
+<div id="head">
+  <h1><strong>{{title}}</strong></h1>
+  <ul class="actions">
+    <li class="minibutton"><a href="{{base_url}}/{{escaped_url_path}}"
+       class="action-view-page">Home</a></li>
+  </ul>
+</div>
+<div id="wiki-history">
+
+  <fieldset>
+  <table>
+    <tbody>
+
+      {{#versions}}
+      <tr>
+        <td class="author">
+            {{>author_template}}
+        </td>
+        <td class="commit-name">
+          <span class="time-elapsed" title="{{date_full}}">{{date}}:</span>&nbsp;
+          {{message}}
+          [{{id7}}]
+          {{#files}}
+          <br>
+          <a href="{{link}}">{{file}}</a>
+          {{/files}}
+        </td>
+      </tr>
+      {{/versions}}
+
+    </tbody>
+  </table>
+  </fieldset>
+</div>
+<div id="footer">
+
+</div>
+</div>