Monitoring emails

[BryceStevenWilley]

Let's us send notifications to an email whenever there's an error log, similar to docassemble's error notification email. Should help uptime, and makes me a lot less nervous about deploying new versions of the server (something I'm going to have do a lot more in the next few months).

Contains a few other refactors as well:

• moves GetEnv to the StdLib class, and consolidates usage (was originally on a EFM module specific class, and copied in a few different places)
• changes some log.errors to log.warns, since they wouldn't really be errors, or something I'd want to be informed of.
• a bug fix to make the /user/ API more intuitive; will now let non-firm users call GET /user/{my-user-id}, instead of only being able to call GET /user/ (the latter usually needs firm access for arbitrary users, but we can tell when the requesting user is the same as the requested user).

Already tested locally. Going to sleep on it, review myself, then merge. Hard to write unit tests (or integration tests) for something like this.