I want to include in MIToS some visualization for Multiple Sequence Alignments like [alignfigR](http://htmlpreview.github.io/?https://github.com/sjspielman/alignfigR/blob/master/vignettes/introduction.html). Is there a way with Plots to do a [heatmap like plot for categorical variables](http://stackoverflow.com/questions/12998372/heatmap-like-plot-but-for-categorical-variables)?