/// md4.rs was too big because of documentation and plenty of examples
/// So, in order to provide documentation without `docs.rs`'s failing
/// generating documentation, dummy codes were made and documentation and
/// examples were moved to hash_md4.rs.
/// keccak.rs was too big because of documentation and plenty of examples
/// So, in order to provide documentation without `docs.rs`'s failing
/// generating documentation, dummy codes were made and documentation and
/// examples were moved to hash_sha3.rs.