bytekind 0.2.0

Containers for bytes that encode their serialization format as generics

# use bytekind::*;
let json = serde_json::json!([1, 2, 3, 4]);
let bytes: Bytes<Plain> = serde_json::from_value(json).unwrap();
assert_eq!(&bytes, &[1, 2, 3, 4]);

let bytes: Bytes<HexString> = bytes.convert();
let hex_string = serde_json::to_string(&bytes).unwrap();
assert_eq!(hex_string, "\"01020304\"");