No longer needed given new autotools world order

With the regular autotools ports now being able to be used not only
for ports building, but also cross-platform development, mark these
two as DEPRECATED, with a one-month expiration date.

Patches for the 3 ports that currently use these have been issued to
their maintainers.

- Set --mandir and --infodir in CONFIGURE_ARGS if the configure script
  supports them.  This is determined by running ``configure --help'' in
  do-configure target and set the shell variable _LATE_CONFIGURE_ARGS
  which is then passed to CONFIGURE_ARGS.
- Remove --mandir and --infodir in ports' Makefile where applicable
  Few ports use REINPLACE_CMD to achieve the same effect, remove them too.
- Correct some manual pages location from PREFIX/man to MANPREFIX/man
- Define INFO_PATH where necessary
- Document that .info files are installed in a subdirectory relative to
  PREFIX/INFO_PATH and slightly change add-plist-info to use INFO_PATH and
  subdirectory detection.

PR:             ports/111470
Approved by:    portmgr
Discussed with: stas (Mk/*), gerald (info related stuffs)
Tested by:      pointyhat exp run

Update to 2.61

Add SHA256

Update and tweak a little for run-time usage.

Assume maintainership.

It's important to note here that these particular versions of autotools
will be left without FreeBSD-specific hacks, so that developers and IDEs
alike will be able to run in a pristine environment, ensuring
cross-platform capability.  The prefix of ${LOCALBASE}/gnu-autotools
will remain untouched, it's merely a case of ensuring that they are
kept up to date.

Approved by:    marcus

At Kris's request, back out the MACHINE_ARCH spelling correction until
after 5.4-RELEASE.

Assist getting more ports working on AMD64 by obeying the
Ports Collection documentation and use 'ARCH' rather than 'MACHINE_ARCH'.

Install .info files by using INFO knob.

Remove man directories as well.

Reported by:    pointyhat via kris

These ports are strange in that they use a non-standard PREFIX.  Make sure to
clean up after them.

Reported by:    pointyhat via kris

Add a missing NO_MTREE.

Add gnu-autoconf, an unhacked version of autoconf-2.59 aimed at developers
that need to create cross-platform software distributions.  This port installs
into ${LOCALBASE}/gnu-autotools, so developers that need to make use of this
version of autoconf can adjust their paths accordingly.

Discussed with: ade