logging.go
func (logger *Logger) Log(level Level, a ...interface{}) {
	logger.log(level, "", a...)
}
func (logger *Logger) Log(level Level, a ...interface{}) {
	logger.log(level, "", a...)
}
func ( logger * Logger ) Log ( level Level , a ... interface { } ) { logger . log ( level , " " , a ... ) }
// Log logs provided message.
Log logs provided message .