Perform persistent store migration if it does not match current managed object model
Perform persistent store migration if it does not match current managed object model

MIT-Mobile/MIT-Mobile-for-iOS,xNUTs/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS,xNUTs/MIT-Mobile-for-iOS