Not on GitHub yet (waiting for krazyshank to update his wrapper to support the files).
Add this in wserver>realm>entities>player>Player.Chat.cs:
Code:
else if (cmd.Equals("who", StringComparison.OrdinalIgnoreCase))
            {
                StringBuilder stringb = new StringBuilder("Players online: ");
                var copy = psr.Player.Owner.Players.Values.ToArray();
                if (copy.Length == 0)
                    psr.SendPacket(new TextPacket()
                    {
                        BubbleTime = 0,
                        Stars = -1,
                        Name = "",
                        Text = "Nobody else is online"
                    });
                else
                {
                    for (int i = 0; i < copy.Length; i++)
                    {
                        if (i != 0) stringb.Append(", ");
                        stringb.Append(copy[i].Name);
                    }

                    psr.SendPacket(new TextPacket()
                    {
                        BubbleTime = 0,
                        Stars = -1,
                        Name = "",
                        Text = stringb.ToString()
                    });
                }
            }