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

CPP/7zip/Compress/BrotliEncoder.h

@@ -1,9 +1,9 @@
-// (C) 2016 Tino Reichardt
+// (C) 2017 Tino Reichardt
 
 #define BROTLI_STATIC_LINKING_ONLY
 #include "../../../C/Alloc.h"
 #include "../../../C/Threads.h"
-#include "../../../C/brotli/brotli.h"
+#include "../../../C/brotli/encode.h"
 #include "../../../C/zstdmt/brotli-mt.h"
 
 #include "../../Common/Common.h"
@@ -29,7 +29,6 @@ struct CProps
   Byte _ver_major;
   Byte _ver_minor;
   Byte _level;
-  Byte _reserved[2];
 };
 
 class CEncoder: