code formatter

- move sample project from `Demo` to `Example`
- move UnitTest project from `Demo` to `Tests`
refactor, rename Classes and methods

- `DCScrollViewContentView`
- `DCScrollViewNavigationView`
- `DCScrollViewNavigationViewCell`
refactor `DCScrollViewNavigationView`

- change Base Class from `UIScrollView` to `UIView`
- rename `dcDelegate` to `delegate`
- move logic for handling touches to `DCScrollViewNavigationView`
separate `DCScrollViewContentView` from `DCScrollView`
code formatter
bundle classes

- delete files and bundle classes to `DCScrollView`
 `DCScrollViewCell`, `DCScrollViewNavigationViewCell`