[m-rev.] for review: split up higher_order.m

[Zoltan Somogyi]

On 2024-02-21 04:04 +11:00 AEDT, "Zoltan Somogyi" <zoltan.somogyi at runbox.com> wrote:
> The only algorithmic change is to check_module_interface.m.
> The split up of higher_order.m has no code changes to review;
> the only things worth looking at are
> 
> - whether the chosen split of the functionality works, and
> - the names of the new modules.

In the absence of a review by then, I intend to commit this
in a couple of hours.

Zoltan.