Mostly it is just passing new parameter here and there. In case
of zero value we fallback to auto selecting port and thus keep
backward compatibility.

Also we need to fix places of auto selected port managment.
We should bother only when auto selected was done that is
when externally specified port is not 0.
Signed-off-by: NNikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>