Consider how to do logging

[jonathanstegall]

There is potential for a ton of logs here. Salesforce queries, WordPress queries, hook usage, cron events, cron failures.

We need to think about how to do this in a sustainable way that works within a distributable plugin. So it needs to not fill up people's admin area with junk, but it does need to be (maybe optionally) available in there.

We need a way to avoid filling up the database to the point that it becomes a performance issue, or overwhelming to the point that it's impossible to find anything helpful.

• purge itself? maybe at configurable intervals?
• be searchable?
• admin configure which events get logged?
• use an existing class like https://pippinsplugins.com/wp-logging/?

We also need to make sure it gets rid of itself in a good way if the plugin is deactivated. No reason to leave that lying around.

[jonathanstegall]

Have a bunch of commits to achieve this. Basic functionality ends with commit a34373eef5a26565ea2919a9906ff143416dc677