Varios cambios y mejoras.

• Continue playing in the mobile app: The game state is now saved when you close the app and restored when you return.
• Autorotate variants: If a tile fits in multiple ways, hold it in place to try alternative rotations.
• The text in the Settings and About screens is now selectable.
• In portrait mode, the game button now disappears while dragging tiles to show the entire grid.
• If you enjoy the game, leave an app review by clicking the review link in the Settings screen.
• Various minor improvements behind the scenes.
