Bump bundled libarchive version to 3.5.2

- Update bunlded libarchive version used on Windows/Mac
- Enable requested zstd support while we are at it. Closes #211

dependencies/zstd-1.5.0/tests/gzip/zdiff.sh

@@ -0,0 +1,48 @@
+#!/bin/sh
+# Exercise zdiff with two compressed inputs.
+# Before gzip-1.4, this would fail.
+
+# Copyright (C) 2009-2016 Free Software Foundation, Inc.
+
+# This program 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.
+
+# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+# limit so don't run it by default.
+
+. "${srcdir=.}/init.sh"; path_prepend_ .
+
+echo a > a || framework_failure_
+echo b > b || framework_failure_
+gzip a b || framework_failure_
+
+cat <<EOF > exp
+1c1
+< a
+---
+> b
+EOF
+
+fail=0
+zdiff a.gz b.gz > out 2>&1
+test $? = 1 || fail=1
+
+compare exp out || fail=1
+
+rm -f out
+# expect success, for equal files
+zdiff a.gz a.gz > out 2> err || fail=1
+# expect no output
+test -s out && fail=1
+# expect no stderr
+test -s err && fail=1
+
+Exit $fail