Services: Kea: DHCPv4/v6: Add single client_class support to DHCP options

[Monviech]

Should theoretically fix issues like these generically: #9912

For: #9942

Matching a DHCP option is optional.

This should match 90% of the usecases, and makes it easy to reason with (if this -> then that, in the same dialog), no complex hierarchies possible.

Send option always:

Send option only to clients who send that option 93 (client arch) and it's a certain data value

Attach to any subnet4/subnet6 and reservation

Configuration example:

{
    "Dhcp4": {
        "subnet4": [
            {
                "id": 1,
                "subnet": "192.168.50.0\/24",
                "next-server": "",
                "match-client-id": false,
                "option-data": [
                    {
                        "name": "domain-name-servers",
                        "data": "192.168.30.1"
                    },
                    {
                        "name": "routers",
                        "data": "192.168.30.1"
                    },
                    {
                        "name": "domain-name",
                        "data": "ad.pischem.com"
                    },
                    {
                        "name": "ntp-servers",
                        "data": "192.168.30.1"
                    },
                    {
                        "code": 3,
                        "csv-format": false,
                        "data": "06060606",
                        "always-send": false
                    },
                    {
                        "code": 4,
                        "csv-format": false,
                        "data": "08080808",
                        "always-send": false,
                        "client-classes": [
                            "b5ba1864-bc3d-43e7-9e8d-b31b34ad59f6"
                        ]
                    }
                ],
                "pools": [
                    {
                        "pool": "192.168.50.100-192.168.50.110"
                    }
                ],
                "reservations": []
            }
        ],
        "client-classes": [
            {
                "name": "b5ba1864-bc3d-43e7-9e8d-b31b34ad59f6",
                "test": "option[7].hex == 0x01010101"
            }
        ]
    }
}