Sheet dismiss modifier

[Wouter125]

First implementation of adding a dismiss modifier that resembles the implementation of Apple. Based on PR #30 of @b0nsun9.

Setup includes;

• Swipe to remove on smallest detent
• Additional threshold of 50 before removing
• Keeping a full animation activated instead of hard removal.

Still need to implement a few more things before merging, but it does the trick.

[Wouter125]

Sorry about this stale PR. I'm mostly working on this during my weekends so...

Anyways. While I was fixing this I noticed some other issues popping up. Currently I rewrote a couple of parts and am soon ready to release V3. It will come with;

1. Improved animations.
2. Several to-do's removed due to reimplementation of scaling.
3. Support for keeping content centered while the card is growing.
4. The Apple CornerRadius view modifier. https://developer.apple.com/documentation/swiftui/view/presentationcornerradius(_:)
5. The Apple Background view modifier. https://developer.apple.com/documentation/swiftui/view/presentationbackground(alignment:content:)
6. Improved Apple interaction modifier. https://developer.apple.com/documentation/swiftui/view/presentationbackgroundinteraction(_:)
7. Additional swipe to dismiss modifier.

[Wouter125]

• Fix alignment of content inside sheet since we now animating on height.

• Fix background animation when moving it up. Currently only the inner contents animate.

• Bring back the bg interaction modifier.

• Optionally fix the issue where the sheet can’t be toggled visible mid-way animation anymore. Would need to store the view offscreen rather than removing it completely right now.