* Rename them to be OpenTK.NMatrix# (instead of Simd.MatrixFloat#x#).
* Remove the Vector2 and Vector4 variants, we'll use the OpenTK types instead (but we'll keep the NVector3 variant, since it's not identical to the OpenTK version).
* Update the API to match their OpenTK counterparts better:
* NMatrix2 and NMatrix3 have a 0-based R#C# scheme for their fields.
* NMatrix4 has a 1-based M## scheme for its fields (i.e. no change).
Rolf Bjarne Kvinge
Timothy Risi