Started refactoring math lib; shorter names.
Renamed all usage of Vector3 to vec3 and Vec3.
Refactoring Vector4. Small refactor on Vector2.
Renamed usages of Vector4 to vec4.
Quaternion is now quat.
Renamed usages of Quaternion to quat.
Renamed Matrix2x2 to Matrix2 and mat2.
Renamed Matrix3x3 to Matrix3 and mat3.
Renamed and the usages of Matrix4x4 to Matrix4 and mat4.
X, Y, Z, and W are now all lowercase.