Disable chatty connection logging by default

[rschlaikjer]

For servers fielding tens/hundreds of concurrent clients, the connect/disconnect logs flood out more useful information.

Disable them by default, but allow re-enabling them if so desired.

[ziyan]

@rschlaikjer Why don't we check existence of log.verbose and use that? This way you can change log level at runtime and allow us to debug in a pinch

[rschlaikjer]

@rschlaikjer Why don't we check existence of log.verbose and use that? This way you can change log level at runtime and allow us to debug in a pinch

I thought about that but seemed hacky. If we think that's fine then sure. I guess fall back to debug if verbose doesn't exist?