Add vector.combine

[appgurueu]

Adds a rather simple function vector.combine. Useful for determining bounds of a set of points by combining vectors using math.min or math.max. Ready for Review.

[SmallJoker]

Why not vector.apply, but with a 3 argument variant? I don't think there's a need for an additional function for this.

[appgurueu]

Why not vector.apply, but with a 3 argument variant? I don't think there's a need for an additional function for this.

Matter of taste. Overloading functions through argument checks is not something I consider particularly clean. It would also (very slightly) hurt performance.

[ghost]

Seems fine to me from a quick look. I tried some valid operations, and as expected from the unit test they worked fine. Then I tested some invalid ones, doing things like generating nans and returning non-numerical types... these resulted in the same as you'd get from a normal vector.new call (makes sense when you look at how the code works), so I'd call that passing.