fixes #1090 move warning about missing checksums from dashboard to sync page

* avoid scaring users for a minor issue
* convert the warning message into a simple info
* simplify algorithm for detection and only search on relevant pages (batch manager + sync page)

admin/batch_manager_global.php

@@ -470,6 +470,15 @@ $template->assign(
    )
  );
 
+if (isset($page['no_md5sum_number']))
+{
+  $template->assign(
+    array(
+      'NB_NO_MD5SUM' => $page['no_md5sum_number'],
+    )
+  );
+}
+
 // +-----------------------------------------------------------------------+
 // |                            caddie options                             |
 // +-----------------------------------------------------------------------+