This is a simple, no-dependency library which implements the hash functions
needed by Bitcoin. These are SHA1, SHA256, SHA256d, SHA512, and RIPEMD160. As an
ancillary thing, it exposes hexadecimal serialization and deserialization,
since these are needed to display hashes anyway.
[Documentation](https://docs.rs/bitcoin_hashes/)
Contributions are welcome, including additional hash function implementations.