Splitting doesn't show split subnets in CIDR

[tecknicaltom]

When using sipcalc to split a network, the output does not show any of the resulting subnets in CIDR format. Instead, the section headers confusingly prints out the CIDR provided on the cmdline. For example:

$ sipcalc -s /17 -u 192.168.0.0/16  | grep /
-[ipv4 : 192.168.0.0/16] - 0
-[ipv4 : 192.168.0.0/16] - 0
-[ipv4 : 192.168.0.0/16] - 0

I see two potential ways to fix this:

1. Add CIDR notation as an output line to print_cidr_info_v4
2. Change the section header to reflect the subnet being printed. (e.g. with the above cmdline you'd see section headers:

   -[ipv4 : 192.168.0.0/17] - 0
   -[ipv4 : 192.168.0.128/17] - 0
   

I can supply a PR with either or both of these changes if you can share which you'd prefer.