Support multiple subnets with the generated dhcpd.conf

[JustinVenus]

Currently the utility only generates a single subnet, even though we have enough information to create multiple subnets.

example:

for the 192.168.100.0 network with the subnet mask 255.255.255.192

Network from to Broadcast Address
192.168.100.0 192.168.100.1 192.168.100.62 192.168.100.63
192.168.100.64 192.168.100.65 192.168.100.126 192.168.100.127
192.168.100.128 192.168.100.129 192.168.100.190 192.168.100.191
192.168.100.192 192.168.100.193 192.168.100.254 192.168.100.255

actual result:
Network from to Broadcast Address
192.168.100.0 192.168.100.1 192.168.100.62 192.168.100.63