skarnet.org UNIX utilities

Rounding out the collection from [http://www.skarnet.org/software/](http://www.skarnet.org/software/).

These are configured to link statically (to skalibs, not libc).

I use a couple of these here and there, mostly [s6-update-symlinks](http://www.skarnet.org/software/s6-portable-utils/s6-update-symlinks.html).