Addition of ecosystem service indicators to the backend service (new histogram variables).
colormap.py creates a jQuery flot/plot compatible hex value
from an ArcGIS .clr file. (This probably belongs in the ArcInfoGrid2Shapefile
project, but the histograms need this function.)
barmap.py associates a histogram keyword with a .clr file value.
These files will be used to generate a data structure, using colormap.py,
that will enable the histogram function to associate the correct legend
color. In the future, this should be accomplished with CSS generated
by CartoDB's built-in classifications--it does not scale very well.