func (b *Base) Warningf(msg string, a ...interface{}) error {
	return b.Log(LevelWarning, nil, msg, a...)
}
func (b *Base) Warningf(msg string, a ...interface{}) error {
	return b.Log(LevelWarning, nil, msg, a...)
}
/*
Warningf uses msg as a format string with subsequent parameters as values and logs
the resulting message to all added loggers at LogLevel.LevelWarning
*/