resolved: remove entry from cache when goodbye packet received

resolved: remove entry from cache when goodbye packet received

RFC6762 10.1 says that queriers receiving a Multicast DNS response with a TTL
of zero SHOULD record a TTL of 1 and then delete the record one second later.

Added a timer event to trigger a callback to clean-up the cache one second after
a goodbye packet is received. The callback also checks for any cache entries
expiring within the next one second and schedules follow-up cleanup callbacks
accordingly.