Logging tweaks to work better as a systemd service

- Main change is log lines no longer have date stamps
- loggers use __name__ now instead of a string literal
Logging warm and fuzzies

- balance_containers always logs when it's finished
- image pull logs when it's finished
- image id is in image pull
- container id is logged on creation
Containers no longer destroyed on shutdown

This was a bad idea. Since wharf is really just a management fronted to docker,
it was really rude to destroy everything in docker when the wharf shuts down.
There's no real reason to do be that disruptive to wharf users. The functionality
has been stubbed out, however, and may be added back with the future with more
flexibility.
The correct VNC port is actually mapped.