as the bootcd* CDs just with the install sets added to
the CD as well.
XXX 1) The implementation of this is rather cludgy (copying sets around),
as our makefs(8) can't put files from multiple directories into
one image -- something that mkisofs can do with 'graft' points
XXX 2) This should be run after 'build.sh release' - It would be nice
if we had a seperate stage to add such hooks in our build framework
