Extend task stats to include information about waiting for user feedback

Right now when task is waiting for user feedback (either by displaying a dialog box or by automated retrying) the task is marked as running, without any information that it is really waiting for something.
That might be especially painful when task is put into auto-retry mode - now it will just display 0B/s copying speed. User have to guess that it is retrying the task and not doing the real job.