Test client initialization using mock WSDL/XSD.
Full test of ping_status().
Proper hashing of password (why? oh well...)
Completed test for ReadOrder.
Test _add_webshop().
Add parse_datetime and test.
Check for required attributes, format datetime.
Work on progress.
We're not going to work with complex types.
Remarks about required fixups / updates to XSD.
Test request and response for prepare_order().
Consistent tests for webshop.