XCode 7, iOS 9:
import EventKit in WatchKit extension: These functions never exists, only comment
import EventKit in iOS app: The functions exists
deprecated? EKEventStore: saveEvent, removeEvent, refreshSourcesIfNecessary
Found this in the header of WatchOS2:
"On WatchOS, saving changes is not supported."
So as with WatchOS2 the WatchKit extension is part of the WatchApp and no longer part of the iOS App you're no longer able to save events inside a WatchKit extension.
Dirk
Yes, I also found it now. Thanks for this answer.