Color maps designed to improve graph readability for readers with
common forms of color blindness and/or color vision deficiency. The
color maps are also perceptually-uniform, both in regular form and
also when converted to black-and-white for printing. This is the
'lite' version of the 'viridis' package that also contains 'ggplot2'
bindings for discrete and continuous color and fill scales and can
be found at <https://cran.r-project.org/package=viridis>.