v3.0.0

⚠️ This is an breaking change and won't support the config file in v2.x.x and before. ⚠️

• You can now use IP address APIs which returns JSON.
• A dedicated switch is added to IPv4 and IPv6. You can only check and update IPv4 or IPv6 now.
• Prettified the configuration file.

---

⚠️ 这是一个大改动，v2.x.x 及过去版本的配置文件将不被兼容 ⚠️

• 你现在可以用返回JSON的IP地址接口了
• 为IPv4和IPv6增加了单独的开关，现在你可以选择只检查和更新IPv4或IPv6
• 配置文件的结构现在变得更合理了