[WIP] Switch to using standard logger

[bchrobot]

Using the standard logger for all output makes it a lot easier to drop the core functionality into other projects beyond the current CLI. click-log integrates logger quite nicely with Click.

[bchrobot]

I think I may have gone too far with replacing click.echo with logger.*. Or not far enough with separating logging levels -- might need some more debug sprinkled in there.

[bchrobot]

In short: stdout is for output, stderr is for messaging.

-- 12 Factor CLI Apps

This makes sense to me. I will get around to updating this eventually.