Websockets: Connect counsellors to users on chat

[schan219]

Users want to talk to counsellors on the chat, so we need to connect a user to a counsellor when there is at least one counsellor online. A counsellor can address many users but a user can only talk to one counsellor at a time. As for the details of how the counsellors should be assigned users, all counsellors online should be able to see a request to connect and can either accept or decline users. When one counsellor accepts a request, other counsellors may not accept the same request.

When a request to connect is accepted, the counsellor and user enter into a chat session. The session ends when one person disconnects from that session.