Sections of abstract polytopes

[vihdzp]

Some code to generate a section of an abstract polytope (from the ranks of the elements and its indices, say) would be nice. It would also allow us to grab concrete elements or element figures (though we might want to do these separately, as most likely the code will be both faster and easier).

[vihdzp]

The code works. It's not optimal in running time (it generates the dual for the entire polytope even when generating a small section), but we can tweak it later.