TwitchConnection.WriteThread check connection

[lexonegit]

TwitchConnection.WriteThread.cs at line 19:
var stream = tcpClient.GetStream();

can sometimes give this error:
InvalidOperationException: The operation is not allowed on non-connected sockets.

Very random, impossible to reproduce. But maybe add something to verify that TCPClient is actually connected before doing anything.

(issue probably exists in TwitchConnection.ReadThread.cs too)

[lexonegit]

Update: this issue is related to poor/unstable internet connection. But how to handle this?