6/6/2002
Added ability to handled data sets with more than one matrix in an input file,
as well as the ability to handle more than one input tree.

8/26/2002
Removed bug in NNI.c 

9/2002
Removed bug in main program in print statement called only in verbose mode.

10/1/2002
Added ability to simply assign OLS or balanced weights on an input topology,
without doing any NNIs.

11/19/2002
Fixed parts of newick.c to make it preserve the exact order of the input
topology.

2/28/2003 
Expanded search of bNNI to retest all edges, rather than only edges adjacent to
changed edge.

8/24/2006
Added the PHYLIP like interface.

9/20/2006
Added BIONJ algorithm.
