this is a relatively stable C library, the only problem is that there are also very old versions (2.2.0 on Fedora 26) around, and it's not quite clear whether they work and how to distinguish them.

We do the latter by checking for link member in vertexRec from planarity/graphStructures.h

CC: @kiwifb @embray @tobihan @infinity0 @isuruf @mkoeppe

Component: build: configure

Author: Dima Pasechnik

Branch/Commit: 604dfac

Reviewer: Isuru Fernando

Issue created by migration from https://trac.sagemath.org/ticket/29063