Add a set of color palettes  #4

I was reading your https://bbc.github.io/rcookbook/ and this is pretty great, but there's an easy step that you could take that would add simplicity and consistency to the plot making process: Take a look at RColorBrewer... it let's you very simply to call out colors as per a variety of themes... perhaps something like this could be done w/ BBC colours? This way one would never have to read a theme sheet, it would be built right in. Helpful?