Add sample for Snap points / Inertia modifiers

[wldevries]

The Swipe Scroller is a nice example, but it would be great to have a simpler example. The composition documentation includes a section on snap points, but the example code does not have enough detail to actually build a ScrollViewer with snap points. It would be great to have this particular example in this sample repository.

https://docs.microsoft.com/en-us/windows/uwp/composition/inertia-modifiers

Issue Type

[ ] Bug Report
[X] Feature Request
[ ] Sample request
[ ] Documentation issue or request
[ ] Other – Please describe:

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