[Framework] Updated framework with new features and bug fixes:

- FormSheet and PageSheet presentation styles on iPad now work out of the box
- Fixed issues when presenting camera view on top of navigation view controller
- Overlay tracking animation more smooth
- Several other bug fixes
[Demo] Updated demo app.

- Added new overlay example. This is the default overlay used in pdf417 app when you don’t specify the overlay yourself. Use it as a reference for creating better overlays for your use cases.
- Demo app now uses navigation view controller for easier testing of this presentation style
[Docs] Updated documentation