title: Create NSManagedObject subclass not generating property after updating to Xcode 6.0
body: <p>After updating to Xcode Version 6.0 (6A313), when I add a new attribute to my xcdatamodeld entry, "Create NSManagedObject subclass" is not adding the new property to the generated header file.  This works fine after closing Xcode 6, and then running Version 5.1.1 (5B1008).  I repeated this process a couple of times with the same results.  Do I need to do something to allow a new Xcode version to properly manage my data models, or recreate them, or is this possibly just a bug with the new Xcode?</p>
  
  <p>Here are the specific steps I took:<br>
  1. Open DataModel.xcdatamodeld in Xcode 6.0 (GM Seed).<br>
  2. Select correct entity<br>
  3. Click + to add new attribute<br>
  4. Enter name and selected Boolean type for new attribute<br>
  5. Editor->Create NSManagedObject subclass<br>
  6. Ensure proper data model is checked, click next<br>
  7. Ensure correct entity is checked, click next<br>
  8. Choose location to save (using root project folder), select Create<br>
  9. Choose "Replace" in dialogue box<br>
  10. Look for variable in generated header file.  Variable not present.<br>
  11. Close Xcode6<br>
  12. Repeat steps 1-10 in Xcode 5.1.1, worked correctly<br>
  13. Repeated this process twice to verify same results<br></p>
  
  <p>Thanks for any help!</p>