Added stub method fetchStoriesSinceLastLoaded which starts by calling the findLatestStoryDate method. My hope is that we'll be able to eventually make a special call to the backend that will fetch only new stories that we haven't already loaded, and will make that call here. This method gets called in view will appear, so any time we return to the homeVC, it should fire off, and fetch the newest stories, including any stories just added by the user. As a result, I've also moved the call for fetchStoriesForRegion to viewDidLoad, since we only want to fetch ALL the stories the first time the app loads. Also, updated the findLatestStoryDate method so that it simply references the self.stories array rather than requiring an array to be passed into it.