Background merge

vigilCoreDatabase.m

- (void)backgroundContextDidSaveNotification:(NSNotification*)notification
{
    for (NSManagedObject *object in notification.userInfo[NSDeletedObjectsKey]) {
        NSLog(@"deleted: %@", object.entity.name);
    }
    // the background moc saved - merge changes
    NSManagedObjectContext *context = [self managedObjectContext];
    void (^mergeChanges) (void) = ^ {
        [context mergeChangesFromContextDidSaveNotification:notification];
    };
    if ([NSThread isMainThread]) {
        mergeChanges();
    } else {
        dispatch_sync(dispatch_get_main_queue(), mergeChanges);
    }
}