Make TutorialModel inherit from NSObject
Make TutorialModel inherit from NSObject

haaakon/Presentation,flooie/Presentation,xuanyi0627/Presentation,tonypham/Presentation,luzefeng/Presentation,tonypham/Presentation,ernestopino/Presentation,ernestopino/Presentation,flooie/Presentation,xuanyi0627/Presentation,luzefeng/Presentation,haaakon/Presentation