updated SisowComponent to siswo.cls5.php as distributed with the WooCommerce plugin v. 3.3.14
- whitespace cleanup
- added status constants
- improved errors/logging
- $sha1 attribute isn't used
- added invoice data attributes
- added RefondRequest, InvoiceRequest, CancelReservationRequest, CreditInvoiceRequest, FetchMonthlyRequest and GetLink methods (untested)
formatting, comments
set testmode