separate Classes

- DCScrollViewContentView
- DCScrollViewNavigationView
bugfix scroll navigation view and dont swich content view

- need to use `-hitTest:withEvent:`

> commit: 052bb58952d90ef21b397474a90e0e413e03a437
> bugfix touch on navigation view, dont scroll
>
> - delete `-hitTest:withEvent:`
> - validate to scroll page on `-touchesEnded:withEvent:`