title: Issue Unknown type name NSManagedObject
body: <p>I'm trying to have a very simple Core Data. I have a ViewController.h like this : </p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  
  @interface ViewController : UIResponder &lt;UIApplicationDelegate&gt;;
  
  @property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext;
  @property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel;
  @property (readonly, strong, nonatomic) NSPersistentStoreCoordinator *persistentStoreCoordinator;
  
  - (IBAction)boutonSave:(id)sender;
  
  @end
  </code></pre>
  
  <p>and a ViewController.m like that : </p>
  
  <pre><code>#import "ViewController.h"
  
  @implementation ViewController
  
  @synthesize managedObjectContext = __managedObjectContext;
  @synthesize managedObjectModel = __managedObjectModel;
  @synthesize persistentStoreCoordinator = __persistentStoreCoordinator;
  
  - (IBAction)boutonSave:(id)sender {
  ViewController *viewController = [[UIApplication sharedApplication] delegate];
  NSManagedObjectContext *context = [viewController managedObjectContext];
  NSManagedObject *newJournee; //THIS LINE IN ERROR
  newJournee = [NSEntityDescription insertNewObjectForEntityForName:@"JourneeDeTravail" inManagedObjectContext:context];
  [newJournee setValue:_displayStart.text forKey:@"debut"];
  [newJournee setValue:_displayEnd.text forKey:@"fin"];    
  </code></pre>
  
  <p>}</p>
  
  <p>But when creating newJournee, I have a red alert "Unknow type name 'NSManagedObject',  did you mean NSManagedObjectModel ?" ??? It's my first Core Data so I certainly missed something obvious to you... but not to me ! Help !</p>