On re-handshake, the client should clear the subscribed channels. #28
Description
When the server asks for a re-handshake, the client should clear its state, including the subscribed channels.
We added a listener for the handshake event, and in OnMessage, we are calling GetChannel('/topic', lastReplyId).Subscribe(). In the event of a re-handshake, GetChannel returns an existing channel from the Channels dictionary with the previously passed replyId and ignores the replyId in the current #call.
After the handshake, it should clear all non-meta channels from the Channels dictionary.
This bug causes this issue:
##27