Bug 505677

SUMMARY
Modifying an event that you organized always sends the updates to the participants, even if you might not want it to be the case.

STEPS TO REPRODUCE
1. Create an event
2. Add participants with their emails
3. Save the event
4. An invitation email is sent to each participants by Korganizer
5. Later on, attend the invitation
6. After the event, you want to update the 'real' duration for instance, or add bonus participants
7. Edit the event, then close the incidence editor

OBSERVED RESULT
8. No matter what, even if the event is already in the past, the updated is pushed to every participants

EXPECTED RESULT
In a perfect world, you should not have to edit past events, but in the real world, you might need to fix a typo, update the real duration, fix the tags that the newest Korganizer keeps mangling with wrongly encoded accents or just deleting altogether, etc.
In that case, you do _not_ want to send an email to every participants when fixing past events.

Ideally, when modifying such event, Korganizer should display a dialog that would ask the user if he wants to send the update to every attendees.