(relation_print, relation_digraph):

(relation_print, relation_digraph):
Relation sizes are of type relation_node, not size_t (this is
merely a doc fix, since the two types are equivalent).
(relation_transpose): Relation sizes are of type relation_node,
not int.
(top, infinity): Now of type relation_node, not int.
(traverse, relation_transpose): Use relation_node, not int.