Deduce a server name when not set in the configuration
The server "Name" in the "[Global]" section of the configuration file is
optional now: When not set (or empty), ngIRCd now tries to deduce a
valid IRC server name from the local host name ("node name"), possibly
adding a ".host" extension when the host name does not contain a dot
(".") which is required in an IRC server name ("ID").
This new behaviour, with all configuration parameters now being
optional, allows running ngIRCd without any configuration file at all.