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/lib/tests/scaffold/70-array-in-struct-init.c

@@ -0,0 +1,56 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 2019 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/>.
+ */
+
+#include <mes/lib.h>
+
+struct foo
+{
+  int field;
+  int array[3];
+};
+
+struct foo foes[] =
+  {
+   {10, {11, 12, 13}},
+   {20, {21, 22}},
+   {30, {31}},
+   {40, {41}},
+   {0}
+  };
+
+int
+main ()
+{
+  for (struct foo *p = foes; p->field; p++)
+    {
+      oputs ("{");
+      oputs (itoa (p->field)); oputs (",");
+      oputs ("{");
+      oputs (itoa (p->array[0])); oputs (",");
+      oputs (itoa (p->array[1])); oputs (",");
+      oputs (itoa (p->array[2]));
+      oputs ("}");
+      oputs ("},\n");
+    }
+  oputs ("{0}\n");
+  oputs ("};\n");
+
+  return 0;
+}