Allow for progressive barchart displays of taxonomy hierarchy by clicking on specific bars

[mkoo]

Once #255 implemented, allow for hierarchically arranged binned histograms. So that clicking on a bar for an Order, chart for Families appears; when clicking on a Family bar, binned by genus chart appears; when clicking on a genus bar, chart of species appears. See original request below:

"When I bin by Order, Family, or Genus, and get a histogram, could you maybe have it be similar to "Location" so that when I click on the bar, I get another bar chart showing all of the Families (for binned by Order), Genera (for binned by Family), and Species (for binned by Genera)?"