Add mes and mescc-tools-extra

mescc-tools-extra contains two important tools:
- cp
- chmod

mes first builds itself from a mes 0.21 seed as used by guix, and then
builds a mes 0.22 and then mes 0.22 using that created mes 0.22.

It does /not/ use bootstrap.sh as we don't have a proper shell at this
point, it has been manually adapted for kaem.

sysa/mes-0.22/module/mes/misc.scm

@@ -0,0 +1,77 @@
+;;; GNU Mes --- Maxwell Equations of Software
+;;; Copyright © 2016,2017,2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
+;;;
+;;; This file is part of GNU Mes.
+;;;
+;;; GNU Mes is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Mes is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Mes.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (mes misc)
+  #:use-module (srfi srfi-1)
+  #:export (%scheme
+            disjoin
+            guile?
+            mes?
+            pk
+            pke
+            warn
+            stderr
+            string-substitute))
+
+(cond-expand
+ (mes
+  (define %scheme "mes"))
+ (guile
+  (define %scheme "guile")))
+
+(define guile? (equal? %scheme "guile"))
+(define mes? (equal? %scheme "mes"))
+
+(define (logf port string . rest)
+  (apply format (cons* port string rest))
+  (force-output port)
+  #t)
+
+(define (stderr string . rest)
+  (apply logf (cons* (current-error-port) string rest)))
+
+(define (pk . stuff)
+  (newline)
+  (display ";;; ")
+  (write stuff)
+  (newline)
+  (car (last-pair stuff)))
+
+(define (pke . stuff)
+  (display "\n" (current-error-port))
+  (newline (current-error-port))
+  (display ";;; " (current-error-port))
+  (write stuff (current-error-port))
+  (display "\n" (current-error-port))
+  (car (last-pair stuff)))
+
+(define warn pke)
+
+(define (disjoin . predicates)
+  (lambda (. arguments)
+    (any (lambda (o) (apply o arguments)) predicates)))
+
+(define (string-substitute string find replace)
+  (let ((index (string-contains string find)))
+    (if (not index) string
+        (string-append
+         (string-take string index)
+         replace
+         (string-substitute
+          (string-drop string (+ index (string-length find)))
+          find replace)))))