iOS 14 issues fix

v0.1.5

Apply paging offset fix only on Xcode 12 (#11)

Some iOS 14 fixes

In preparation for iOS 14, some SwiftUI components and wrappers may need to be updated. This is the first step toward that, with some small fixes.

ScrollableView: Bugfix

ContentSize calculation fix for the ScrollableView component.

PageView and PageControl

Includes SwiftUI wrappers for UIPageViewController and UIPageControl, bindable from outside and using collection of Identifiable plus content view builder as data source.

Allow Animated Binding Changes

Allow Dispatching of Actions to be animated (#6)

I finally implemented the default arguments for subscripts. They are a bit weird, as they can only be at the end, and the argument names are removed. I had to fiddle a bit to make this work. 

But I like it a lot now :)

This allows to create bindings like this:

```swift
// Dispatches `select(preset: $0)` from an `withAnimation` block
viewModel.binding[\.selectedPreset, .animated] { .select(preset: $0) }
// Same as above, but does not trigger animation
viewModel.binding[\.selectedPreset] { .select(preset: $0) }
// Does not allow to change the value, only getting.
viewModel.binding[\.selectedPreset]
```

UIExtensions v0.1.0

Hello world!