Revert "Delete the events that represent exceptions to a recurring event when deletin...

Revert "Delete the events that represent exceptions to a recurring event when deleting the recurring event."

Eh, better to delete each one individually, as the exceptions may have different
resources and/or attendees that need to be dealt with.
This reverts commit e6f350ebd53a80bddd2e31352dca86f6c32a31f4.