Simple & time saver

The plugin is simple and save a lot of time when upgrading a theme or a plugin.
As mentioned earlier by a user, the setting of a destination backups folder it is a must, since this folder can be added to exclusion list on our favorite backup scripts.
For the moment for personal user, I did modify the code, line 133 in custom-plugin-upgrader.php for $zip_path. If not possible to add some settings for the plugin, maybe put if function exists in the private function caj_create_backup in future upgrades so one can use functions.php to override this function and set his own path.
Thank you, great work !