(/=) Make AsyncNetwork more robust

-on the simulator, it behaves consistently how it should.
-there were two bugs in the previous implementation: alive was not set
to true before restarting, and the onSendFailure used the wrong
callback handler to post the response (i think this was causing the
„not scrolling down“ issues)
-on the phone, it also seems to work but it is necessary to send two
messages before the system recovers. (this is not the case in the
simulator)
(+) Copy AsyncNetwork to 'chat' task

(+) Reuse MessageLogic in ChatLogic