Puns.h and Puns.m save methods

Pun is a subclass of NSManagedObject which implements the basic behavior required of a Core Data model object, like access to the managed object context (MOC). The MOC is responsible for several managed objects and also responsible for persisting them to a persistent store like a database. The terminology is explained in this video. The data from the database is loaded in the punsArray using the NSFetchedResultsController. The instance of NSFetchedResultsController also registers to receive change notifications on the managed object context that holds the fetched objects. Any change in the context that affects the result set will then be reflected in the table view.