hcid

Holochain base32 encoding scheme for keys, agents, identifiers, etc.

```rust extern crate hcid;

fn main() { let enc = hcid::HcidEncoding::withkind("hcs0").unwrap(); let key = enc.encode(&[0; 32]).unwrap(); asserteq!("HcSciaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", key); let buffer = enc.decode(&key).unwrap(); asserteq!([0; 32].tovec(), buffer); } ```