Prevent WP users from being trashed/deleted

- return actual rowCount of affected rows for bulk actions (based on PDO last statement)
- prevent removal of WP Users segment relationship with subscribers.

lib/Models/Model.php

@@ -124,7 +124,8 @@ class Model extends \Sudzy\ValidModel {
       }
     }
 
-    return $total;
+    $last_statement = $orm->get_last_statement();
+    return $last_statement->rowCount();
   }
 
   function duplicate($data = array()) {