Upgrade ws library

[birgitta410]

The ws library is quite out of date, at the time of opening this issue, the latest version is 3.1.0.

Found some breaking changes:

ws.upgradeReq is gone,

wss.on('connection', function(ws) {
    console.log('connecting to /' + ws.upgradeReq.url); // will fail
    ...
});

instead:

wss.on('connection', function(ws, req) {
    wsUrl = req.url;
    console.log('connecting to ' + wsUrl);
    ...      
});

Secondly, the way this implements paths for websocket servers is not supported anymore:
websockets/ws#885
Changing this is a bit more tricky.