Changelog for blake3-0.1.1

Version 0.1.1

Enabled AVX-512, AVX2 and SSE-4.1 support.

On x86_64 Linux, Darwin and Windows, assembly implementations are used. Elsewhere, C intrinsics are used.

The avx512, avx2 and sse41 Cabal flags can be used to disable these optimizations.
Documentation fixes.

Initial version.
Using upstream C code from [https://github.com/BLAKE3-team/BLAKE3](https://github.com/BLAKE3-team/BLAKE3) version 5651ce7ee0b0ad2f577beef7efcef87e2f39fbe2.