Console logging backend

This is a logging implementation for log that is designed for console programs. It is easy to configure, optionally integrates with structopt for configuration, and can write log messages to stderr in concert with indicatif for coordinated logging and progress reporting.

Example

You can use this as follows:

```rust use log::; use happylog::;

fn main() -> () { initialize(LevelFilter::Info).unwrap(); info!("info logging message"); } ```