Support using proxy dial-up connection to GitHub. (#46)

config/config.go

@@ -13,6 +13,7 @@ type Config struct {
 	Blacklist BlacklistConfig
 	Whitelist WhitelistConfig
 	RateLimit RateLimitConfig
+	Proxy     ProxyConfig
 }
 
 type ServerConfig struct {
@@ -62,6 +63,11 @@ type RateLimitConfig struct {
 	Burst         int    `toml:"burst"`
 }
 
+type ProxyConfig struct {
+	Enabled bool   `toml:"enabled"`
+	Url     string `toml:"url"`
+}
+
 // LoadConfig 从 TOML 配置文件加载配置
 func LoadConfig(filePath string) (*Config, error) {
 	var config Config