Custom registration notice template

Hello Justin,
thanks for writing this plugin.

Can you please make the code in network-subsite-user-registration.php#L250 a tiny bit more flexible like for the signup page by replacing the hardcoded path to plugin’s page-registration-notice.php file with a call to $this->find_custom_template( 'page-registration-notice.php' );?

I thought about proposing a PR at Github, but the repo there doesn’t seem to be up to date with the www.remarpro.com plugins repo.

Thanks!