Log Message:
Change from using ${OPSYS} to looking for /usr/include/blacklist.h
to determine whether to use the blacklistd feature.  This allows
for automatically picking up new OSes that provide blacklistd as
well as ignoring older versions of NetBSD and FreeBSD that don't
have blacklistd.

Add UseBlacklist to M4 config generator.  This means that you can
turn it on by doing something like:

LOCAL_CONFIG
...
define(`confUSE_BLACKLIST', `True')dnl
...

It is set to false as the feature is experimental having just been
created.

Ride previous PKGREVISION bump as it was less than an hour ago.