TabBarController.selectedViewController issue  (#407)
TabBarController.selectedViewController issue  (#407)

* - HeroCompatible added
- UIView+Hero translation WIP

* - Added HeroCompatible protocol and constrained HeroExtension
- Adopted UIView+Hero, UIViewController+Hero to new constrained extension
- Updated Examples and Source files with changes

* - Code refactoring: .hero.ID replaced with .here.id

* - Resolved issue for custom tab bar controller when selected item cannot be determine correctly

lkzhao/Hero,lkzhao/Hero