This change is focused on fixing rotating loggers in Windows
where it was failing due to Windows file semantics disallowing
the rotation while that file was still being open (because we
had multiple lumberjacks pointing to the same file).
This is fixed by ensuring the initialization happens only once.
This addresses a bug where logging would not be output when
cloudflared was run as a Windows Service.
That was happening because Windows Services have no stderr/out,
and the ConsoleWriter log was failing inside zerolog, which would
then not proceed to the next logger (the file logger).
We now overcome that by using our own multi writer that is resilient
to errors.
Igor Postelnik
Nuno Diegues
Areg Harutyunyan
Rachel Williams
Dalton