Added Table to global settings

Added Table to UI global settings view
Added Table to wg conf template
Added Table to settings model
Added Table with default value `auto` to config util
Updated README

model/setting.go

@@ -11,6 +11,7 @@ type GlobalSetting struct {
 	MTU                 int       `json:"mtu,string"`
 	PersistentKeepalive int       `json:"persistent_keepalive,string"`
 	ForwardMark         string    `json:"forward_mark"`
+	Table               string    `json:"table"`
 	ConfigFilePath      string    `json:"config_file_path"`
 	UpdatedAt           time.Time `json:"updated_at"`
 }