The bigger goal was being able to set up build in a way
that would allow for images (with configs and logs) be
deposited in per-IMAGE_NAME subdirectories of IMAGEDIR;
that's not done yet but a part of it is ready.

NB: in BUILDDIR, symlinking the just-built image is now
replaced with symlinking the IMAGEDIR since its location
is then predictable thus .gitignore-able for further work
on a generated profile, and more documentable as well.
It's not a hard change though, if you miss the image link
just drop me a note (or a commit).