func (g *Glg) Warnf(format string, val ...interface{}) error {
	return g.out(WARN, format, val...)
}
func (g *Glg) Warnf(format string, val ...interface{}) error {
	return g.out(WARN, format, val...)
}
func ( g * Glg ) Warnf ( format string , val ... interface { } ) error { return g . out ( WARN , format , val ... ) }
// Warnf outputs formatted Warn level log
Warnf outputs formatted Warn level log