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* Added ``dms_diffselection`` program.
* Added ``--colormap`` and ``--overlay3`` options to ``dms_logoplot``
* Make ``dms_merge`` remove sites indicated as *None* when in *renumber* mode, added ``--skipfirstline`` option, and made commas an allowable separator.
* Increased number of colors allowed by *PlotMutCountFracs* (used by ``dms_summarizealignments``)