jksk/NLCoreData — pull request #13 by miniak (2013-06-18 12:52:44+00:00)
Title: Fix crash in [NSManagedObjectContext rebuildAllContexts]

_mainContextTokenRef
_storeContextTokenRef
_backgroundContextTokenRef

may be NULL if you haven't accessed

[NSManagedObjectContext mainContext]
[NSManagedObjectContext storeContext]
[NSManagedObjectContext backgroundContext]