Publish Didiator v0.2.0

[SamWarden]

• Fix query handler example in README
• Fix example with aiogram: use outer middleware registration, instead of inner
• Add Event entity
• Refactor handlers: add HandlerTypes for specific handlers
• Add EventHandler
• Refactor exceptions: add typehints
• Refactor dispatchers: add typehints
• Add EventObserver interface
• Refactor base middleware: add wrap_middleware function
• Add EventMediator interface
• Refactor dispatchers implementations: improve typehints
• Add EventObserver implementation
• Add di_state passing to values of di_builder in DiMiddleware
• Add events to LoggingMiddleware
• Add the EventObserver to the Mediator implementation
• Add lazy formatting to LoggingMiddleware
• Add middlewares property to EventObserver
• Add chained error raising to dispatchers
• Refactor typehints in EventObserver
• Fix DiBuilder: remove default None value for the execute method
• Add pylint config to pyproject.toml
• Upgrade aiogram example with EventObserver usage
• Add events description to README
• Bump didiator version to v0.2.0