Utilities for encoding and decoding frames.
Contains adapters to go from streams of bytes, [`AsyncRead`] and
[`AsyncWrite`], to framed streams implementing [`Sink`] and [`Stream`].
Framed streams are also known as `transports`.
[`AsyncRead`]: AsyncRead
[`AsyncWrite`]: AsyncWrite
[`Sink`]: futures_sink::Sink
[`Stream`]: futures_core::Stream