This directory contains test classes for virtual
topologies. In fhe following the number of nodes 
needed and some explanations are annotated:


class                  no. of nodes (min-max)           annotation
------------------------------------------------------------------
cart                        6-6                         not impl.
dimscreate                  1-inf                       not impl.
graph                       4-4                         not impl.
map                         1-inf                       not impl.
sub                         6-6                         not impl.
