Update Service.php

SoapClient will drop the first parameter if you pass it in as a list of arguments. See: http://stackoverflow.com/questions/3812765/param0-disappearing-in-soap-request-in-php-using-soapclient-class

This bug was introduced here: https://github.com/artisaninweb/laravel-soap/commit/b2ff17cd006f6040f8b2bb0bc0bab272c2aa896f

Passing the parameters as a single array resolves the issue.