Update the asynchronous examples to fix reconnecting and have it work
Warn if the socket was closed such as if RabbitMQ dies without a Close frame
Give more info in the ChannelClosed exception
Change the constructor signature for BlockingConnection, block open/close callback methods

- Remove callback option since it is not support
- Override the add_on_open_callback/add_on_close_callback methods since BlockingConnection does not support them
- Change the exception raised on remote close or socket disconnect in BlockingConnection to ConnectionClosed