Add logic to check if pages even exist.

There was a problem with the dashboard page when checking for latest pages if there were no pages in the user/pages folder.

classes/admin.php

@@ -499,6 +499,10 @@ class Admin
         $pages = $this->grav['pages'];
 
         $latest = array();
+        
+        if(is_null($pages->routes())){
+            return;
+        }
 
         foreach ($pages->routes() as $url => $path) {
             $page = $pages->dispatch($url, true);