expose time of last action in stats.

js/pixl/server.js

app.get('/stats', function(req, res) {
	var stats = {
		users: wss.clients.length,
		pixls: Object.keys(world).length
		pixls: Object.keys(world).length,
		last_active: new Date(last_active).toISOString()
	};
	res.setHeader('Content-Type', 'text/plain');
	res.send(JSON.stringify(stats, null, "  "));
var wss = new ws.Server({server: server});
var last_active = 0;
var world = {};
wss.on('connection', function(socket) {
				client.send(msg);
			}
		});
		last_active = Date.now();
	});
});