Display netmask in IP section

[in-journey]

Describe the solution you'd like
For VPS (and perhaps other services) it would be nice to have netmask information visible in IP section.

For the moment we only have:

• IPv4
• IPv6
• IPv6 Gateway

I had to go through docs to get IPv6 netmask, which in the end was invalid (ovh/docs#379).
I also couldn't find any information about IPv4 netmask. This also created small problem for me. Had to get proper one with help of whois.

It might also be nice to have IPv4 Gateway information there, just to keep everything clear in one place.

Describe alternatives you've considered

• API - no luck, no netmask information there,
• Docs - outdated.