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/contrib/linux-kernel/btrfs-benchmark.sh

@@ -0,0 +1,104 @@
+# !/bin/sh
+set -e
+
+# Benchmarks run on a Ubuntu 14.04 VM with 2 cores and 4 GiB of RAM.
+# The VM is running on a Macbook Pro with a 3.1 GHz Intel Core i7 processor and
+# 16 GB of RAM and an SSD.
+
+# silesia is a directory that can be downloaded from
+# http://mattmahoney.net/dc/silesia.html
+# ls -l silesia/
+# total 203M
+# -rwxr-xr-x 1 terrelln 9.8M Apr 12  2002 dickens
+# -rwxr-xr-x 1 terrelln  49M May 31  2002 mozilla
+# -rwxr-xr-x 1 terrelln 9.6M Mar 20  2003 mr
+# -rwxr-xr-x 1 terrelln  32M Apr  2  2002 nci
+# -rwxr-xr-x 1 terrelln 5.9M Jul  4  2002 ooffice
+# -rwxr-xr-x 1 terrelln 9.7M Apr 11  2002 osdb
+# -rwxr-xr-x 1 terrelln 6.4M Apr  2  2002 reymont
+# -rwxr-xr-x 1 terrelln  21M Mar 25  2002 samba
+# -rwxr-xr-x 1 terrelln 7.0M Mar 24  2002 sao
+# -rwxr-xr-x 1 terrelln  40M Mar 25  2002 webster
+# -rwxr-xr-x 1 terrelln 8.1M Apr  4  2002 x-ray
+# -rwxr-xr-x 1 terrelln 5.1M Nov 30  2000 xml
+
+# $HOME is on a ext4 filesystem
+BENCHMARK_DIR="$HOME/silesia/"
+N=10
+
+# Normalize the environment
+sudo umount /mnt/btrfs 2> /dev/null > /dev/null || true
+sudo mount -t btrfs $@ /dev/sda3 /mnt/btrfs
+sudo rm -rf /mnt/btrfs/*
+sync
+sudo umount /mnt/btrfs
+sudo mount -t btrfs $@ /dev/sda3 /mnt/btrfs
+
+# Run the benchmark
+echo "Compression"
+time sh -c "for i in \$(seq $N); do sudo cp -r $BENCHMARK_DIR /mnt/btrfs/\$i; done; sync"
+
+echo "Approximate compression ratio"
+printf "%d / %d\n"                                                             \
+  $(df /mnt/btrfs --output=used -B 1 | tail -n 1)                              \
+  $(sudo du /mnt/btrfs -b -d 0 | tr '\t' '\n' | head -n 1);
+
+# Unmount and remount to avoid any caching
+sudo umount /mnt/btrfs
+sudo mount -t btrfs $@ /dev/sda3 /mnt/btrfs
+
+echo "Decompression"
+time sudo tar -c /mnt/btrfs 2> /dev/null | wc -c > /dev/null
+
+sudo rm -rf /mnt/btrfs/*
+sudo umount /mnt/btrfs
+
+# Run for each of -o compress-force={none, lzo, zlib, zstd} 5 times and take the
+# min time and ratio.
+# Ran zstd with compression levels {1, 3, 6, 9, 12, 15}.
+# Original size: 2119415342 B (using du /mnt/btrfs)
+
+# none
+# compress: 4.205 s
+# decompress: 3.090 s
+# ratio: 0.99
+
+# lzo
+# compress: 5.328 s
+# decompress: 4.793 s
+# ratio: 1.66
+
+# zlib
+# compress: 32.588 s
+# decompress: 8.791 s
+# ratio : 2.58
+
+# zstd 1
+# compress: 8.147 s
+# decompress: 5.527 s
+# ratio : 2.57
+
+# zstd 3
+# compress: 12.207 s
+# decompress: 5.195 s
+# ratio : 2.71
+
+# zstd 6
+# compress: 30.253 s
+# decompress: 5.324 s
+# ratio : 2.87
+
+# zstd 9
+# compress: 49.659 s
+# decompress: 5.220 s
+# ratio : 2.92
+
+# zstd 12
+# compress: 99.245 s
+# decompress: 5.193 s
+# ratio : 2.93
+
+# zstd 15
+# compress: 196.997 s
+# decompress: 5.992 s
+# ratio : 3.01