func (l *stdLogger) Infof(format string, v ...interface{}) {
	if l.Level <= logger.LevelInfo {
		l.setStdPrefix(logger.LevelInfo)
		l.printfStd(format, v...)
	}
}
Info logs a info message with format
package standard
import (
	"log"
	"os"
	"github.com/takama/k8sapp/pkg/config"
	"github.com/takama/k8sapp/pkg/logger"
)
const UTC = "+0000 UTC "
func New(cfg *logger.Config) logger.Logger {
	var flags int
	prefix := "[" + config.SERVICENAME + ":" + cfg.Level.String() + "] "
	if cfg.Out == nil {
		cfg.Out = os.Stdout
	}
	if cfg.Err == nil {
		cfg.Err = os.Stderr
	}
	if cfg.Time {
		flags = log.Ldate | log.Ltime | log.Lmicroseconds
		if cfg.UTC {
			flags = flags | log.LUTC
		}
	}
	return &stdLogger{
		Level:  cfg.Level,
		Time:   cfg.Time,
		UTC:    cfg.UTC,
		stdlog: log.New(cfg.Out, prefix, flags),
		errlog: log.New(cfg.Err, prefix, flags),
	}
}
type stdLogger struct {
	logger.Level
	Time   bool
	UTC    bool
	stdlog *log.Logger
	errlog *log.Logger
}
func (l *stdLogger) Debug(v ...interface{}) {
	if l.Level == logger.LevelDebug {
		l.setStdPrefix(logger.LevelDebug)
		l.printStd(v...)
	}
}
func (l *stdLogger) Debugf(format string, v ...interface{}) {
	if l.Level == logger.LevelDebug {
		l.setStdPrefix(logger.LevelDebug)
		l.printfStd(format, v...)
	}
}
func (l *stdLogger) Info(v ...interface{}) {
	if l.Level <= logger.LevelInfo {
		l.setStdPrefix(logger.LevelInfo)
		l.printStd(v...)
	}
}