Bitcoin base58 encoding

This crate provides encoding and decoding of base58 strings as defined by the Bitcoin ecosystem including the checksum.

There are a bunch of crates on crates.io that implement base58 encoding and decoding. The more obviously named ones differ from this crate because:

1. bitcoin-base58 is transpiled from the C++ code in Bitcoin Core as part of a large long-term transpilation project, whereas this crate is a pure Rust implementation intended to be production-ready and to provide an Rust-idiomatic API.

2. base58 implements parsing but does not validate checksums (see base58check). It may be appropriate in cases where performance is more important than safety. Appears unmaintained.

3. base58check Adds checksum to the base58 crate and depends on sha2 for hashing. Appears unmaintained.

This crate uses bitcoin_hashes when hashing to calculate the checksum.