[Feature] WCT Carousel element

[jamesmcroft]

Description

Add support for the Windows Community Toolkit Carousel element.

The implementation should support the collection of child items with the ability to select items.

[jamesmcroft]

Exploring this, similar to #21, the WCT Carousel control doesn't expose the selected item which will make it difficult to update the control's state in an element wrapper for this framework.

Logged issue 3506 on the WCT to rectify this with PR 3507.

Once this has been merged, it will be possible to complete this work.