Added subscription limit in order to avoid mass subscriptions

lib/Config/Migrator.php

@@ -134,6 +134,9 @@ class Migrator {
       'last_name tinytext NOT NULL DEFAULT "",',
       'email varchar(150) NOT NULL,',
       'status varchar(12) NOT NULL DEFAULT "' . Subscriber::STATUS_UNCONFIRMED . '",',
+      'ip varchar(32) NULL,',
+      'confirmed_ip varchar(32) NULL,',
+      'confirmed_at TIMESTAMP NULL,',
       'created_at TIMESTAMP NULL,',
       'updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,',
       'deleted_at TIMESTAMP NULL,',