0.9.1: Rolling back protocol version

I had made various protocol changes when I was initially developing and accidentally released a rolled forward version v3, where v3 is what I wanted to be released as v1. If you've deployed this, please update both the client and server and restart the server and you should be golden. You will get errors about deprecated protocol versions if you do not update both together.

Documenting "cert_logfile" and client port in example config.