Reminders backend
The kongressac code is an untested copy-paste of the alarm check application of Calindori. Moreover, no alarms are registered (the corresponding code in EventController::addEdit has been commented out).
We should try to use the new, mobile friendly, powerdevil features for alarm scheduling - kclock has already made use of them. I don't know if this approach can be used for desktop. If that's now the case, we should make kongressac to work for mobile, otherwise, get rid of it or keep whatever is relevant.