SimpleGraphCatalog.pl - A catalog of all simple graphs with fewer than 8 vertices.
This macro defines the $graphCatalog hash. It has 8 keys (0, 1, ..., 8). the value of each key is a reference to an array containing all possible graphs (up to isomorphism) with that number of vertices.
Graphs are represented as a reference to an array of arrays which are suitable for passing to "simpleGraph" in SimpleGraphs.pl to create a GraphTheory::SimpleGraph object.
For example, $graphCatalog{3}[3] is
[ [ 0, 1, 1 ], [ 1, 0, 1 ], [ 1, 1, 0 ] ]