prepare a duplicate backend loader suitable for QOF

[David Hampton]

On Fri, 2005-08-12 at 23:59 +0100, Neil Williams wrote:

> Are these errors related to not being able to find GNCBook and 
> GNCObjectForeachBackend?
> 
> GNCBook is QofBook ... 
> I've already changed those over whilst working on CashUtil.

Instead of making this change to the business code and probably causing
you sync headaches, I committed a one-liner to backend/file/gnc-xml.h.
Just revert it when you commit your business changes.

David