Use example documentation IP address ranges

[dougbtv]

Currently we have general IP addresses:

      "ipam": {
        "type": "whereabouts",
        "range": "2001::0/116",
        "gateway": "2001::f:1"
      }

These should be updated to use the official example ranges.

[sureshkrishnan]

Please use this prefix for IPv6 examples

2001:db8::/32

and use one of these prefixes for IPv4 examples

192.0.2.0/24 198.51.100.0/24 203.0.113.0/24

These are reserved blocks expressly for the purpose of documentation (and hence avoiding clashes with any user assigned addresses).

[jdavidson2021]

Did anyone test this example on a pod to make sure the pod can actually reach the gateway?

  "ipam": {
    "type": "whereabouts",
    "range": "2001::0/116",
    "gateway": "2001::f:1"
  }

The gateway is outside of the configured network range. Shouldn't there be a requirement for the gateway to be within the assigned range?