minor cleanup
cause error when the programs location cannot be retrieved
extend description of the Windows service
add exit message for Windows and code formatting
add support to answer 1.0.0.127.in-addr.arpa and the similar .ip6.arpa PTR request

the hope is that some requesters will react faster when they get an answer to this specific question and do not wait for a timeout first
update changelog
do not build with NAT-PMP/UPnP support by default
update changelog