This version of mcrypt requires autoconf 2.50 or newer. Accordingly,
use that instead of the old autoconf. Add a pre-configure target
to run autoconf, because bsd.port.mk only supports the old autoconf.

Left to its own devices, the program now installs files with strange
names such as /usr/local/man/man1/i386-portbld-freebsd4.4-mcrypt.1
and /usr/local/bin/i386-portbld-freebsd4.4-mcrypt. To avoid this,
the whole installation now happens in a do-install target in the
port's Makefile, which also does the former post-install tasks.

Install supplementary documentation, unless NOPORTDOCS is defined.

Use EXAMPLESDIR.

The mdecrypt utility was removed. It has been replaced by a -d
option to mcrypt.

Drop USE_LIBTOOL and add back GNU_CONFIGURE.

PORTVERSION remains nil, since this did not build.

Add a warning about my laziness.