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/7s-struct-short.c

@@ -0,0 +1,74 @@
+/* -*-comment-start: "//";comment-end:""-*-
+ * GNU Mes --- Maxwell Equations of Software
+ * Copyright © 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/>.
+ */
+
+
+struct foo
+{
+  char c;
+  short bar;
+  short baz;
+};
+
+struct bar
+{
+  char bar;
+};
+
+struct foo global_f = { 0, 11, 22 };
+struct bar global_b = { 11 };
+
+int i = 0x11223344;
+
+struct foo foes[2] = { {0, 1, 2}, {0, 3, 4} };
+
+int
+main ()
+{
+  if (global_f.bar != 11)
+    return 1;
+
+  if (global_f.baz != 22)
+    return 2;
+
+  struct foo f = { 0, 44, 55 };
+
+  if (f.bar != 44)
+    return 3;
+
+  if (f.baz != 55)
+    return 4;
+
+  if (global_b.bar != 11)
+    return 5;
+
+  if (foes[0].bar != 1)
+    return 6;
+
+  if (foes[0].baz != 2)
+    return foes[0].baz;
+
+  if (foes[1].bar != 3)
+    return 8;
+
+  if (foes[1].baz != 4)
+    return 9;
+
+  return 0;
+}