[python][bbox] register default ctor

frackit/python/geometry/boundingbox.hh

@@ -44,6 +44,7 @@ void registerBoundingBox(py::module& module)
             "xmin"_a, "ymin"_a, "zmin"_a, "xmax"_a, "ymax"_a, "zmax"_a);
     cls.def(py::init<const Point&, const Point&>(), "firstCorner"_a, "secondCorner"_a);
     cls.def(py::init<const Box&>(), "box"_a);
+    cls.def(py::init<>());
 
     // dimensionality properties
     registerDimensionProperties(cls);