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/doc/README.md

@@ -0,0 +1,25 @@
+Zstandard Documentation
+=======================
+
+This directory contains material defining the Zstandard format,
+as well as detailed instructions to use `zstd` library.
+
+__`zstd_manual.html`__ : Documentation of `zstd.h` API, in html format.
+Click on this link: [http://zstd.net/zstd_manual.html](http://zstd.net/zstd_manual.html)
+to display documentation of latest release in readable format within a browser.
+
+__`zstd_compression_format.md`__ : This document defines the Zstandard compression format.
+Compliant decoders must adhere to this document,
+and compliant encoders must generate data that follows it.
+
+Should you look for resources to develop your own port of Zstandard algorithm,
+you may find the following resources useful :
+
+__`educational_decoder`__ : This directory contains an implementation of a Zstandard decoder,
+compliant with the Zstandard compression format.
+It can be used, for example, to better understand the format,
+or as the basis for a separate implementation of Zstandard decoder.
+
+[__`decode_corpus`__](https://github.com/facebook/zstd/tree/dev/tests#decodecorpus---tool-to-generate-zstandard-frames-for-decoder-testing) :
+This tool, stored in `/tests` directory, is able to generate random valid frames,
+which is useful if you wish to test your decoder and verify it fully supports the specification.