StrChunk: zero-copy UTF-8 buffers for I/O

Announcing a pre-release of strchunk, a library crate building on bytes to provide efficient containers for working with UTF-8 encoded Unicode text in asynchronous, multithreaded I/O stacks.

The crate is intended to be used in a text codec layer for Tokio, enabling zero copy decoding when the source byte stream is UTF-8 or ASCII.