Adding lib/functions

[Akim Demaille]

How about starting shipping replacement files with Autoconf?  This has
been something many people have wished for a long time, including
myself.  It would really help sync'ing many things.  I'm not sure how
to install these files automatically in a tree yet, but that can be
done in a later step.

Each time I thought about this issue, it fell on something I never
quite understood: how come there are several portability trees?  I'm
referring to those Paul and Jim typically use, and to libiberty.

Anyway, currently the test suite would appreciate having fnmatch and
more importantly, getloadavg.

Thoughts?