public class NeighborJoiningTree
extends SimpleTree
constructs a neighbor-joining tree from pairwise distances
Saitou, N., and Nei, M., (1987) The neighbor-joining method: A new method for reconstructing phylogenetic trees. Mol. Biol. Evol, 4(4):406-425,
public NeighborJoiningTree(DistanceMatrix m)
construct NJ tree
m - distance matrix