DebugMiddleware feature

[danylott]

Add DebugMiddleware, which will print all nats activity of microservice.
Template of DebugMiddleware:

class DebugMiddleware(Middleware):
    def __init__(self, logger):
        self.logger = logger

    async def send_any(self, subject: str, message, send_func, *args, **kwargs):
        self.logger.info(f"Sent to {subject} message {message}")
        return await send_func(subject, message, *args, **kwargs)

It Will be cool to have a chance to select log level, also add listen_any function, and to choose, which (listen or send or both) to debug