Client applications crashes on startup, if daemon is not available

[Rafał Cieślak]

In case the client is unable to connect to the daemon after trying to run it (which may happen due to:
  - packaging problems
  - binary file unavailability
  - daemon crashing on startup due to some bug (this actually may be a likely case)
  - invalid daemon installation
  - problems with DBus connection),
it should a) try again and again, every few seconds or b) notify the user about the problem.

As for now, it crashes instead, with
   AttributeError: 'TrophyinfoWindow' object has no attribute 'ask_to_start_daemon'
because the notification has been recently removed.

It may be possible to easily join both a) and b) by using following procedure:
1) Try starting the daemon, if it succeeds - continue normally,
2) If it does not, set appropriate message in the status bar,
3) Wait several seconds, and proceed to 1).