logger.go
func MustGetLogger(module string) *Logger {
	logger, err := GetLogger(module)
	if err != nil {
		panic("logger: " + module + ": " + err.Error())
	}
	return logger
}
func MustGetLogger(module string) *Logger {
	logger, err := GetLogger(module)
	if err != nil {
		panic("logger: " + module + ": " + err.Error())
	}
	return logger
}
// MustGetLogger is like GetLogger but panics if the logger can't be created.
// It simplifies safe initialization of a global logger for eg. a package.