Support machine parsable log output

[elliot-u410]

Currently log output is colored which looks great when reading it yourself, but makes it hard to use the logs in a log streaming system. At the very least it would be nice to have the option to disable colored output. Even better would be to have JSON or similar format as an option.

[cbrit]

Thanks for the feedback, @elliot-u410. We'll be working on improving diagnostic options for Steward soon and this is a good feature.