Remove LoggerAwareTrait from Email class

[dafriend]

I would like this considered because the Email class creates a Logger instance when it's instantiated. I'm trying to devise an EmailHandler for the Logger class which would require an instance of the Email class. I sure you can see the endless loop that is formed.

It doesn't seem like removing the LoggerAwareTrait would affect Email much. It only makes one call to the resulting logger object. Switching that call to using the common function log_message seems a good substitute for $this->logger->log...

If this PR is merged I've got a working EmailHandler ready to go.

[MGatner]

I think using log_message() directly is actually desirable and consistent with other libraries, as we establish logging early as a service and the helper function will always rely on that. I would like @lonnieezell or @jim-parry to take a look as well but I'm good with this change. This library's days are numbered but it would be good to have it feel at least consistent for release.