Added list replication to clients in the example.

- Fixed an issue with the server only allowing for one stream. Added a
dedicated queue to process streams from clients.
- Clients currently poll and don’t do not perform any sort of
prediction. Ideally we would send events from the server to client, but
I believe this would require a separate service with Thrift.
Removing ListAppState.

- This is basically replaced with our Thrift representation.