added tracking response

snipcart/snipcart.go

@@ -49,6 +49,8 @@ type SnipcartOrder struct {
 	Country        string         `json:"shippingAddressCountry"`
 	PostalCode     string         `json:"shippingAddressPostalCode"`
 	Phone          string         `json:"shippingAddressPhone"`
+	TrackingNumber string         `json:"trackingNumber"`
+	TrackingUrl    string         `json:"trackingUrl"`
 	Items          []SnipcartItem `json:"items"`
 }