Custom derive support for the flexiber crate

With #[tlv(slice)] set, Encodable should work for fields implementing AsRef<[u8]>, and Decodable should work for fields implementing TryFrom<[u8]>, even if the field is not Decodable or Encodable.

flexiber

Encoding and decoding of BER-TLV as described in ISO 7816-4, without allocations.

Follows the approach taken in der, and then in simple-tlv.

License

^{flexiber is licensed under either of Apache License, Version 2.0 or MIT License at your option.}
_{Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.}