Refactor logging and add support for quiet flag

[whwright]

trafficstars

• Replace local log_info and log_warning functions with a module logger and logger.info/logger.warning
• Add support for --quiet flag by setting the level on the logger
• Resolves #190
• This also does a little bit of setup for #182 as a module logger would be required to set different log handlers for different log levels

[whwright]

Any thoughts on this change?

[josegonzalez]

Mind making this log-level instead, like in #199?

[whwright]

Mind making this log-level instead, like in #199?

Yeah I can make that change. Thanks!

[josegonzalez]

Mind rebasing?

[whwright]

I apologize for abandoning this - thank you to everyone who got it across the finish line!