Sub-protocol support broken

[ppmathis]

Currently the sub-protocol support is broken in websocket.io (when the hybi protocol is used). The problem is in the 'ws' package / library. It was fixed there in version 0.4.22, but websocket.io still requires 0.4.20 in its dependencies.

It should be atleast changed to 0.4.22 to support sub-protocols properly again.

Fix in 'ws' library for reference: websockets/ws@b0be70f