It is generally not a good idea to have multiple IP addresses on the same
interface unless managing their relative priorities via metrics etc.
During an outage, I noticed that with multiple IP addresses,
Linux was using the old obsolete one to send out packets,
which does not work with the ISP.
With this change,
we still hold on to IP addresses for as long as possible,
but no longer.
fixes issue #57
Michael Stapelberg