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/keep.sh

@@ -0,0 +1,51 @@
+#!/bin/sh
+# Exercise the --keep option.
+
+# Copyright (C) 2013-2016 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 fooooooooo > in || framework_failure_
+cp in orig || framework_failure_
+
+fail=0
+
+# Compress and decompress both with and without --keep.
+for k in --keep ''; do
+  # With --keep, the source must be retained, otherwise, it must be removed.
+  case $k in --keep) op='||' ;; *) op='&&' ;; esac
+
+  gzip $k in || fail=1
+  eval "test -f in $op fail=1"
+  test -f in.gz || fail=1
+  rm -f in || fail=1
+
+  gzip -d $k in.gz || fail=1
+  eval "test -f in.gz $op fail=1"
+  test -f in || fail=1
+  compare in orig || fail=1
+  rm -f in.gz || fail=1
+done
+
+cp orig in || framework_failure_
+log=$(gzip -kv in 2>&1) || fail=1
+case $log in
+  *'created in.gz'*) ;;
+  *) fail=1;;
+esac
+
+Exit $fail