Slightly reoder startup steps, and enhance logging

Slightly reoder startup steps, and enhance logging

- Show name of configuration file at the beginning of start up.
- Add a message when ngIRCd is ready, including its host name.
- Show name of configuration file on REHASH (SIGHUP), too.
- Change level of "done message" to NOTICE, like "starting" & "ready".
- Initialize IO functions before channels, connections, clients, ...