Fix secure WebSocket server on embedded Unity server build

Improve certificate support for embedded Unity server build

Add support for secure WebSocket server

Update compatibility with DarkRift2 2.6.0

Add custom UnityClient for WebSocket connection

Add support for WebSocket connection over TLS

Fix always passing true to base dispose method in WebSocketServerConnection

Fix client connection not unsubscribing WebSocket callbacks on disconnect

Remove wrongly setting connection state to disconnected before it truly disconnects

Fix setting wrong remote endpoint for WebSocket connection

Make accessing connections dictionary thread safe

Update readme

Add WebSocket client for non WebGL builds

Add all server NetworkListener .dll files

Create DarkRift 2 WebSocket Listener