Implement 10 seconds timeout for CONNECT_RESPONSE

[mdbergmann]

From spec:

After sending the connection request, the KNXnet/IP Client shall wait for the host protocol dependent
time CONNECT_REQUEST_TIMEOUT (= 10 seconds) for the response frame from KNXnet/IP Server.
After that period of time, any received response frame shall be ignored by that client until it starts another
connection request.