A basic base64 encoder / decoder for Rust.
==========================================
``` Rust
let input_vector: Vec<u8> = String::from("Hello World").into_bytes();
let result_string: String = encode(&input_vector);
```
``` Rust
let input_string: String = String::from("SGVsbG8gV29ybGQ=");
let result_vector: Vec<u8> = decode(&input_string);
```