Add input for SSL mail address
We would like to have an additional field at "Web Domain" -> "SSL" to set up a custom mailaddress. Currently postmaster@$domain is used hardcoded:
lib/classes/letsencrypt.inc.php:305:
$letsencrypt_cmd = $letsencrypt . " certonly -n --text --agree-tos --expand --authenticator webroot --server $acme_version --rsa-key-size 4096 --email postmaster@$domain $webroot_args";