Add Vector2/3/4i.MAX and MIN

[KoBeWi]

Closes godotengine/godot-proposals#7348

[AThousandShips]

Let's add MIN while we're at it, as per this

[kleonc]

Let's add MIN while we're at it, as per this

Indeed. In case of float vectors VectorN.INF can be used for both min/max limits respectively (-VectorN.INF for min). In case of integer vectors VectorNi.MIN is not the same as -VectorNi.MAX and hence it makes sense to add both of them.

[akien-mga]

Thanks!