Add QuicTimeoutClosedChannelException which will be used to fail writ…

[normanmaurer]

…es for streams when the Channel was closed because of a idle timeout

Motivation:

To make it easier to debug we should fail queued writes on the streams with a special ClosedChannelException in case of a timeout.

Modifications:

• Use QuicTimeoutClosedChannelException if writes are failed because the connection is timed out
• Add unit test for timeout

Result:

Easier to debug connection close causes