Remove the underscore from the no_shipping module name and code.

[JasperVeerman]

Please remove the underscore from the no_shipping module name, class name and class->code property.

The underscore in the no_shipping class code property breaks the shipping estimate ajax functionality on the frontend.

On frontend shopping cart estimate ajax postback, the value no_shipping_no_shipping will be incorrectly parsed into ($module, $class) array bij the OrderManager.setSelectedShipping() function (lib\common\services\OrderManager.php). As a result the no_shipping selection gets lost and the default shipping method is selected.

    public function setSelectedShipping($shipping) {
        if ($this->isShippingNeeded() && (strpos($shipping, '_') !== false)) {
            list($module, $method) = explode('_', $shipping);