FloatingIPPoolConf improvement

[chenchun]

Currently, configuring multiple pod subnets for the same node subnets is redundant and not clear. e.g.

[{
	"nodeSubnets": ["10.0.0.32/32", "10.0.0.48/32"],
	"ips": ["192.168.0.2~192.168.0.254"],
	"subnet": "192.168.0.0/24",
	"gateway": "192.168.0.1"
}, {
	"nodeSubnets": ["10.0.0.32/32", "10.0.0.48/32"],
	"ips": ["192.168.1.2~192.168.1.254"],
	"vlan": 3,
	"subnet": "192.168.1.0/24",
	"gateway": "192.168.1.1"
}]

I propose adding a FloatingIPPoolConfV2 to rewrite it into

[{
	"nodeSubnets": ["10.0.0.32/32", "10.0.0.48/32"],
	"podSubnets": [{
		"ips": ["192.168.0.2~192.168.0.254"],
		"subnet": "192.168.0.0/24",
		"gateway": "192.168.0.1"
	}, {
		"ips": ["192.168.1.2~192.168.1.254"],
		"vlan": 3,
		"subnet": "192.168.1.0/24",
		"gateway": "192.168.1.1"
	}]
}]