avx2 float3 added
added normalize_magnitude
added divide fast to float3 may copy to float4
move static spheremesh to drawSphere (initialize on first use) so platform has a chance to load the math backend
new /= operator in point4f
_calcClipSpaceAABB in pssm no longer uses radius just transform points into light space and do min max
_roundProjection matrix also optimized.