Add logging framework

[jamescurtin]

Closes #204

Easiest to review by commit.

Note that there will be two new files that are created in the root of the repo containing all log messages:

• logs/django.log
• logs/root.log

The first will contain log messages that are created by django itself, and the second will contain anything emitted by a logger.<log_level>('some message') line. Log rotation is enabled by default (to avoid eating up all disk space on the host with an ever-growing log file).

The format looks like:

Which gives you information about the log level used, when the log was emitted, the module and function (along with the line number of the log line) that emitted the message, followed by the message itself.

Note the new additions to .env.example, which will also need to be carried over to the deployment's .env file. (Note the enum of possible levels: only logs at the level set in the config file (or higher) will make it into the log file--everything with a lower level is dropped. This is nice for things like logger.debug("some message"), because you can leave them in the code and they wouldn't be printed on the production service where the log level might be INFO, for example, but would be printed when you're developing in debug mode. (As compared to a print that's emitted all the time, or needs to constantly be commented and un-commented out)

I converted over all existing prints to logs using whatever log level.

[jamescurtin]

The --wait flag means that this will move onto the next command as soon as all of the containers are up, rather than needing to wait a fixed 60 seconds (even if the containers start up sooner). The timeout prevents this from hanging forever in case something is wrong.

[iragm]

Awesome work! logger.exception is handy, I didn't know about that one. It may take some getting used to use %s instead of f-strings but makes sense.