dhcpv4: added more comments
dhcpv4: send NAK to broacast address
dhcpv4: log reply in a more precise way
Merge pull request #23 from mehlis/nak-to-broadcast

dhcpv4: send Nak to broadcast address
dhcpv6-ia: add logging
Fix compilation errors in last commit
dhcpv4: fix manual dhcp-ranges
Merge remote-tracking branch 'upstream/master'