The updated Netty-socketio adds compatibility with
socket.io-client >= 1.3.

The resource by default now includes the total stats. A user parameter
has been added to request user specific data.

This change intends to restore compatibility with ARSnova Overlay.

A NotFoundException was mistakenly thrown when the Session was set to
null via Socket.IO. Additionally, the user count was sent before it
had been updated.

Closes GH-13.

Added few pp Attributes to SessionInfo. Requests for Public Pool Sessions now return SessionInfo instead of Session.

Closes GH-12.

Closes GH-11.

#14448