2-element structure that can be used to represent positions in 2d-space, or any other pair of numeric values.
Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur. Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md) Copyright (c) 2017-2018 Godot-D contributors
Vector used for 2D Math.