Sheet, Alert and Disappear improvements. Bugfixes.

• Fixed the order in which alert dismisses relative to the action performed
• Fixed some cases in which if/else blocks would not update the views properly
• Improve sheet dismiss detection
• Improve .onDisappear coverage of dismiss flows
• Action sheet now works properly in iPad using popover style
• Added keyboardDismissMode to List and ScrollView
• Added fonts title2 and title3
• Other bugfixes