[Class] PersistentChatEndpoint [Description] 
An endpoint which is the basis for all communication with the Persistent Chat server. This endpoint represents a single connection to a single persistent chat server, using an existing LocalEndpoint instance. This endpoint encapsulates references to all active ChatRoomSession instances to which the user has joined, and provides a access to a variety of management services, functionality for browsing the catalog of available chat rooms, and methods for reviewing chat history. (See PersistentChatServices)