Add 3d math classes

[katamaritaco]

❗ Added a checklist here:

• vec4
• mat4

[mjneil]

I'm going to do mat3, you can do any of the ones that involve 3d

[mjneil]

As far as implementation, we want vecs to be represented as objects, so they have properties like myVec.x myVec.y myVec.zand the mat objects would as an array

[katamaritaco]

Alright cool. I will try to find some time soon to look into those.

[katamaritaco]

I would assign myself but it looks like I can't

[Squeakrats]

idk why I cant assign you