completed all options of float3 and float4 functions in isas and math_c neon still to be done but that will be on mac.
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
mac implementation had _mm_div (x86 intrinsic)