Only two gradients were not incorporated:
http://soliton.vm.bytemark.co.uk/pub/cpt-city/gmt/tn/GMT_cyclic.png.index.html
http://soliton.vm.bytemark.co.uk/pub/cpt-city/jjg/hatch/tn/diag5.png.index.html
Added the function find_cpt.
Renamed the existing gradients to the new names, for instance,
“inferno” is now “mpl_inferno”.
Added a dataset with the names of the colour gradients.