Need []byte Base64 encoding/decoding

JSON byte[] must be transmitted as base64 (default) or some other non-json-violating format since byte[] can contain quotes, colons, brackets symbols used by json spec.

[]byte Serialize:
--> first Base64.encode(in, Base64.DEFAULT)

[]byte Deserialize:
--> Base64.decode(in, Base64.DEFAULT)

Having the above auto support would be great and inline with other JSON parsers.

Start by locating the library's []byte serialization and deserialization entry points and any existing tests for byte values. Compare the current JSON handling with the requested Base64.DEFAULT encode/decode behavior; done means automatic round-trip support without emitting invalid JSON.

Written by the indexing model from the issue text.