Using IP Address Set

To facilitate the configuration of IP addresses according to sets, for configurations that use ip/subnet, IP address sets can be specified for easy maintenance. The specific method is as follows:

Use ip-set to configure the set file, such as
```
ip-set -name cloudflare -file /etc/smartdns/cloudflare-list.conf
```
The format of cloudflare-list.conf is one IP address per line, such as:
```
1.2.3.4
192.168.1.1/24
```
Use IP address sets for options with ip/subnet configurations, simply configure ip/subnet as ip-set:[set name], such as:
```
ignore-ip ip-set:cloudflare
ip-rules ip-set:cloudflare -whitelist-ip
ip-alias ip-set:cloudflare 192.168.1.1
```