System.Numerics vectors support

[danfma]

Hello,

I noticed that version 3 has its own implementation of Vector2 for math, rather than using the Vector2 from System.Numerics. Is there a specific reason for this? This is one of the reasons I was considering this library instead of Aether.Physics2D.

[Zonciu]

This is a very first alpha version, the primary goal is to get it to work correctly, I'm still thinking about how to make it deterministic. The v3 Clang version use SIMD to achieve deterministic, I haven't test it in .NET.
If the SIMD deterministic solution works in .NET, I only need to maintain one project, otherwise I have to maintain two projects.