New lightmapper

-Added LocalVector (needed it)
-Added stb_rect_pack (It's pretty cool, we could probably use it for other stuff too)
-Fixes and changes all around the place
-Added library for 128 bits fixed point (required for Delaunay3D)

editor/plugins/canvas_item_editor_plugin.cpp

@@ -6161,7 +6161,7 @@ bool CanvasItemEditorViewport::can_drop_data(const Point2 &p_point, const Varian
 						   type == "ViewportTexture" ||
 						   type == "CurveTexture" ||
 						   type == "GradientTexture" ||
-						   type == "StreamTexture" ||
+						   type == "StreamTexture2D" ||
 						   type == "AtlasTexture" ||
 						   type == "LargeTexture") {
 					Ref<Texture2D> texture = Ref<Texture2D>(Object::cast_to<Texture2D>(*res));