Enhance the SOAP messaging API

Summary

The SOAP messaging API is xoap based and does not follow the most modern practices. This can be improved.

What is the expected correct behavior?

Code similar to the one below should be possible:

const auto& my_message = soap_command("Configure").add_parameter("run", 111);
my_message.add_parameters({{"scan_info", scan_info_bag}});
send_soap_message(destination_application, my_message);