[Feature Request] Support multiple log handler groups under one logger instance

[Embers-of-the-Fire]

Brief

Add support for multiple log handlers to forward log into different log assembly line.

Why?

It's a common senario to print logs to multiple outputs with different config.

Example API

This is merely a simple demonstration; the specific API selection requires further consideration.

Logger logger = Logger();
LoggerHandler fileHandler = LoggerHandler(
  printer: SimplePrinter(),
  filter: ProductionPrinter(LogLevel.Info),
  output: FileOutput("foo.log"),
);
logger.addHandler(fileHandler);
LoggerHandler consoleHandler = LoggerHandler(
  printer: PrefixPrinter(PrettyPrinter()),
  filter: DevelopmentPrinter(LogLevel.Info),
  output: ConsoleOutput(),
);
logger.addHandler(consoleHandler);

And, when calling log functions, e.g. logger.i("hello world!"), the output will be forwarded to both handler.

This could be implemented with two separate Logger with a manager now.

Reference

See python's logging module for more (possible) use cases.