Missing business/technical codes in upload output

[sumbricht]

The output of download orders contains all necessary information for debugging:

{
	orderData,
	orderId,

	technicalCode,
	technicalCodeSymbol,
	technicalCodeShortText,
	technicalCodeMeaning,

	businessCode,
	businessCodeSymbol,
	businessCodeShortText,
	businessCodeMeaning,
}

For upload orders, there is however only very limited output, which doesn't allow the user to even see whether the call succeeded:

[transactionId, orderId]

Therefore I'd like to propose changing the return value of Client.upload to the object below. For backwards compability I would even propose keys '0', '1' and the iterator; this should then not even require any code changes for current users of the library:

{
	transactionId,
	orderId,

	technicalCode,
	technicalCodeSymbol,
	technicalCodeShortText,
	technicalCodeMeaning,

	businessCode,
	businessCodeSymbol,
	businessCodeShortText,
	businessCodeMeaning,

	// for backwards compatibility with the earlier return value [transactionId, orderId]:
	'0': transactionId,
	'1': orderId,
	[Symbol.iterator]: function*() {
		yield transactionId
		yield orderId
	},
}

I'll create a PR for these changes but I am of course open to discuss :-)