Setting up networking now returns error instead of dying.
Registered indira_sup and indira_listener_sup processes.

It turned out to be easier to hack through Indira with this, and because of
indira_router Indira can't spawn multiple instances in a single VM anyway.
Syslog module made returning errors on errors.
Added closing the af_unix port on write error.
Silenced syslog logs a lot and allowed local syslog to be restarted.

Silencing concerns mainly the recognized operational logs, like application
start/stop or process crashes.