Major changes, including Brotli and Lizard

- update of zstd-mt library
- add brotli v0.6.0
- add lizard v2.0
- xxhash is from zstd for lz4, lz5 and lizard now
- update also the documentation, where needed

C/zstdmt/README.md

@@ -1,8 +1,48 @@
 
-# Multithreading Library for [LZ4], [LZ5] and [ZStandard]
+# Multithreading Library for [Brotli], [Lizard], [LZ4], [LZ5] and [ZStandard]
 
-- this library is used as a threading wrapper for zstd, lz4 and lz5
-- zstandard has it's own now, maybe I should switch to it
-- homepage of zstdmt is: https://github.com/mcmilk/zstdmt
+## Description
+- works with skippables frame id 0x184D2A50 (12 bytes per compressed frame)
+- brotli is supported the same way, it will encapsulate the real brotli stream
+  within an 16 byte frame header
 
-/TR 2017-05-17
+## Generic skippable frame definition
+
+- the frame header for [Lizard], [LZ4], [LZ5] and [ZStandard] is like this:
+
+size    | value             | description
+--------|-------------------|------------
+4 bytes | 0x184D2A50U       | magic for skippable frame
+4 bytes | 4                 | size of skippable frame
+4 bytes | compressed size   | size of the following frame (compressed data)
+
+
+## [Brotli] frame definition
+
+- the frame header for brotli is defined a bit different:
+
+size    | value             | description
+--------|-------------------|------------
+4 bytes | 0x184D2A50U       | magic for skippable frame (like zstd)
+4 bytes | 8                 | size of skippable frame
+4 bytes | compressed size   | size of the following frame (compressed data)
+2 bytes | 0x5242U           | magic for brotli "BR"
+2 bytes | uncompressed size | allocation hint for decompressor (64KB * this size)
+
+
+## Usage of the Testutils
+- see [programs](https://github.com/mcmilk/zstdmt/tree/master/programs)
+
+## Usage of the Library
+
+- see [lib](https://github.com/mcmilk/zstdmt/tree/master/lib)
+
+
+[Brotli]:https://github.com/google/brotli/
+[LZ4]:https://github.com/lz4/lz4/
+[LZ5]:https://github.com/inikep/lz5/
+[ZStandard]:https://github.com/facebook/zstd/
+[Lizard]:https://github.com/inikep/lizard/
+
+
+/TR 2017-05-24