This has effectively been a no-op during the 5.7 release series and
nobody has yelped (other than being slightly confused about its
purpose). Remove it as an option, since the home dir of the privsep user
is always used as the actual privsep directory anyway.

found this testing on OpenBSD itself :)

- add closefrom fallback for OS X / Linux systems, extracted from sudo,
but without the optimized versions, since they cannot work in a
chroot environment (and we're not performance critical here.)
- enable detecting libtls
- conditionally enable https constraint support

Layout build machinery closer to LibreSSL to make code sharing easier.
Split the big Makefile.am into src/compat.

Make a copy of __progname on start to avoid setproctitle clobbering it
later. Check if the OS supports __progname and emulate if unavailable.
- from OpenSSH.
Thanks to Paul B. Henson for reporting the setproctitle emulation issue
and Jonas 'Sortie' Termansen for suggesting __progname emulation.

Add a post-install check to ensure that PRIVSEP_PATH is really empty.

Fixes #3, thanks to @gitisihara for providing the initial patch and
testing.

reported by Loganaden Velvindron

Call the compat code and select the correct emulation mode.
Remove the string encoding support, since we have fixed inputs for the
title string.

- add OS X privsep user creation instructions from jasper@
- update install instructions to be the same everywhere
- remove outdated compiler flags

There is no standard SIN_LEN, unlike SIN6_LEN.

Allow overriding the user and the config file paths for ntpd.
This also adds back --privsep-path from OpenNTPD, which really only
changes the installation instructions from 'make install', since ntpd
always uses the home directory of the ntpd user.
This borrows from the Darren's portable OpenNTPD and from OpenSSL, add
credits and a license.

This makes it easier to see what is supported by each OS, and to improve
them individually.

ensure we get HAVE_ defines set by autoconf

Well, support may be too concrete of a term. There is a lot that is
missing in OS X, and not everything can be implemented with portability
shims. The time APIs in OS X seem to have frozen with NeXTSTEP and never
advanced with POSIX.

EAI_NODATA has been made obsolete.
Properly detect MD5Init in -lmd

Remove dependency on libcrypto, include hash headers in a nicer way.

First attempt at building a new OpenNTPD portable project, based on the
latest OpenBSD source.