In some cases the license-identification header was missing,
so I added that as well. Replaced the remaining headers that
specifically identified "Versions 3.13.7 and higher".
Makefiles and the build system were deliberately excluded.
Allows handling of complex situations like a package
build where some libraries are in a staging area,
but will be copied to the same final location.
eg.
LINKER_ORIGIN_ROOT=/usr/lib/epics:/build/mymodule
Where build TOP is /build/mymodule
Use Linux specific linker trick to allow relocation
of built tree.
relative rpath
use $ORIGIN to reference libraries in other modules
by relative path.
fix rel. RPATH
