comms/gkermit: update to 2.01

Version 1.00 : 25 December 1999
Version 2.00 : 26 May 2021

Version 2.00 is identical to 1.00 except that the source code has
been tailored to build successfully on modern Unix platforms.

November 14, 2021... G-Kermit 2.01 - a few more adjustments to our
ever-changing Unix APIs.

  .................................
  Wed May 26 08:47:48 2021:
  In the years following the initial rlease of this program, which was
  designed to be eternal, the C libraries and header files changed and
  changed and changed to the extent that in 2021 G-Kermit 1.0 ccan't be
  built at all an most Unix platforms, and even on those where a functional
  executable is generated, dozens or hundreds of warnings are issued.
  This, for code that generated zero warnings or errors when compiled
  in 1999.  Thus version 2.0 of May 26, 2021.  The only changes are:

  1. The version identification just below, and:
  2. The inclusion of four previously unneeded header files in gkermit.h.

  .................................
  Mon Nov 15 08:31:48 2021:
  From Kenji Rikitake, two patches added to gkermit.h for macOS with Xcode:

  1. macOS with Xcode has no <malloc.h>
  2. macOS with Xcode has the prototype of sleep() in <unistd.h>
  Conditional if(n)def with __APPLE__ flag, dedicated for macOS.

  It seems unistd.h is now required on many platforms; I now #include it
  in all builds by default; to suppress the #include on platforms that
  don't have unistd.h, do: make "KFLAGS=-DNOUNISTD" ...


(rhialto)