Event delivery from app extensions about swiftclient

[palmin]

In case anyone else runs into similar problems I had to do two things to solve this.

I had to take care to call TelemetryManager.initialize on the main thread as the thread that launches a file provider has no run-loop breaking the timer that sends out events.

To make sure unsent events are cached when extension closes I had to manually send out notifications in NSFileProviderExtension.invalidate() making it look like the app was closing.

#if os(macOS)
        NotificationCenter.default.post(name: NSApplication.willTerminateNotification, object: nil)
#elseif os(iOS)
        NotificationCenter.default.post(name: UIApplication.didEnterBackgroundNotification, object: nil)
#endif

[winsmith]

Fantastic, thank you!