Add support of custom parameters. #43
Description
For example in PayPal Express
'PAYMENTREQUEST_0_INVNUM'=>$this->getInvoiceNumber(),
'PAYMENTREQUEST_0_CUSTOM'=>$this->getCustomInfo(),
{{ message }}
For example in PayPal Express
'PAYMENTREQUEST_0_INVNUM'=>$this->getInvoiceNumber(),
'PAYMENTREQUEST_0_CUSTOM'=>$this->getCustomInfo(),