I want to merge an application program and an IAP loader for
first-time programming of a flash controller.

Both programs are completely separate projects, and later
(once the chip has been programmed) all IAP updates only
require the application code, so I really don't want to put
the sources together.

I just need to combine these two HEX files each time we
produce a series of this product, so always the latest version
of application and loader are programmed into the chip.
I thought such a simple and generic program should be
available somewhere out there...