Proposed patch for contrib/cube

Hi,

I use the cube datatype a fair bit, and one thing I have always wanted
is the ability to do this:

pg=# select cube_from_arrays('{1,2,3}'::float[], '{3,5,6}'::float[]);
cube_from_arrays
---------------------
(1, 2, 3),(3, 5, 6)
(1 row)

That is - build a cube by specifying 2 arrays, one for the UR
coordinate, one for LL.

I hope people find this useful, and if so, we can add it to contrib/cube.

Source is attached.

Thanks,

Joshua Reich
(jdigittl on #postgresql)