QFix ChannelsStore.publish
qfix optimize imports
remove some prints
Fix ChannelsStore.publish call args
QFix ChannelsStore.publish event msg
add TODO "add methods create_chatroom/remove_chatroom/etc"
Fix ChannelsStore.publish "RuntimeError: set changed during iteration"
change wamp_example. add channel 'chat:room'
Merge branch 'wamp2' into rework-broker