Four-cube test case
Fix some warnings - minor changes
Commenting out a test that fails
API change : the AbstractVertexSignature now has a new abstract method to convert edge labels to colors
Copy/paste of the simple graph implementation with added edge colors
Change colors to r and b, and test bipartite complete and complete graphs bicolored by chessboard
After much struggle, force mvn to do the right thing for once and not include the test implementations