Creates a new order in the system. Even though an order is created successfully, the response can return an array
named "validationErrors" containing errors that will need to be addressed. Note that Basic Authentication is required for all requests
as such, make sure to provide the Authorization header with a valid value. Should you choose to provide a callback url by
using the 'WebhookUrl' field, we will send a HTTP POST request to that URL with a JSON payload containing the OrderId when
specific events occur on the order.

CallerInfo.UserId and CallerInfo.Email are mutually exclusive. One must be present, but both cannot be used at the same time.