Only supports "deflate" and "none" compression for now.
Also, add a few clarifications to the archive_read.3 manpage as
requested by William Dean DeVries.
is present for FreeBSD. If you "make distfile" on FreeBSD, you will
soon have a tar.gz file suitable for deploying to other systems
(complete with the expected "configure" script, etc). This latter
relies (at least for now) on the GNU auto??? tools. (I like autoconf
okay, but someday I hope to write a custom Makefile.in and dispense
with automake, which is somewhat odious.)
As part of this, I've cleaned up some of the conditional
compilation options, added make-foo to construct archive.h dynamically
(it now contains some version constants), and added some useful
informational files.
