Fix some bugs with the position of the image in the scrollview
The pictureViewController is not using an Image object as its information for the picture, it is more generic now.

The refactor was done because of saving the images to NSUserDefaults. NSUserDefaults cannot save custom objects.
Helper method to make the segue generic for iPhone and iPad
Save recent viewed pictures to NSUserDefaults
Implement recents.

The recent visited picture are saved in NSUserDefaults and displayed in the RecentsTableViewController
Fix bug on iPad with reloading the recents
Sort the places by name