[Renderers/DX11] Add DirectX11 Renderer

[cugone]

I'd love to add this to my game engine. However it is built on top of native Win32 and DirectX 11. I cannot use SDL or raylib. I currently have ImGui integrated for debugging and editor UIs (they have a DirectX 11 backend available) but for actual game UI it is pretty lackluster and it seems Clay is a nice solution.

[nicbarker]

Great idea, I think even just gathering some examples from other's approaches could be very useful!