cash_addr format implementation inspired by cashaddrjs.
```rust use cash_addr::{encode, decode, AddressType};
let data = [0xF5, 0xBF, 0x48, 0xB3, 0x97, 0xDA, 0xE7, 0x0B, 0xE8, 0x2B, 0x3C, 0xCA, 0x47, 0x93, 0xF8, 0xEB, 0x2B, 0x6C, 0xDA, 0xC9]; let prefix = "bitcoincash"; let addr_type = AddressType::P2PKH;
let address = encode(prefix, addrtype, &data).unwrap(); asserteq!(address, "bitcoincash:qr6m7j9njldwwzlg9v7v53unlr4jkmx6eylep8ekg2");
let (prefix, addrtype, hash) = decode(&address).unwrap(); asserteq!(prefix, "bitcoincash"); asserteq!(addrtype, AddressType::P2PKH); assert_eq!(hash, data); ```