Implement logging/tracing in `saito-rust`

[clayrab]

We could use a real logging library, it would be nice to be able to have log levels and be able to pipe log message easily.

[escapedcat]

• Blog Post: Logging in Rust
• https://github.com/j4ckcyw/rust-logging-samples
• https://docs.rs/env_logger/0.9.0/env_logger/
• https://docs.rs/pretty_env_logger/0.4.0/pretty_env_logger/