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This new version has a few breaking changes needed when adding support for
redis pub/sub.
* Processors do not have direct_messages attribute anymore. Instead,
broadcast_message attribute should be used.
* pubsub.customize has the following changes
- add_subscriber
- get_subscribe_direct_messages
- get_publish_direct_messages
+ get_subscribe_broadcast_message
In order to generate a message from SubscriberProcessor
get_subscribe_broadcast_message should be overridden. The default behavior is
not to generate any messages.
* topic.customize has deliver_event_messages method which should be used to
cutomize which websocket connections should receive the message (this takes
the role which was performed by direct_messages attribute and the second
element of the tuple returned by rpc calls)
* The second element on the tuple returned by rpc calls need to be either None
or a BroadcastMessage
* Added support for redis pubsub, allowing multiple tornwamp instances to
communicate.