This commit cleans up a bunch of code in the event handler,
making it much easier to understand (IMO). I feel much better
about how we handle connecting and disconnecting callbacks. Before,
we were actually allowing a bunch of callbacks to stay connected and
get cleaned up. Now, we actually properly disconnect them.
- Merge WebSocketProtocol into WebSocketServer
- Having them separated was not doing anything productive
- Request: Move SessionPtr to RequestHandler
- Less copying to do for batch requests
- Fully modularize EventHandler
- Make BroadcastEvent a stored callback that WebSocketServer sets
- Return early on high volume events to avoid unnecessary compute
- These events will only generate a json object when it is actually
needed
