Improve documentation of cartopy.feature.NaturalEarthFeature

[ketakopter]

Description

I'm having a hard time trying to plot terrain data. Anyway, to the point: the documentation of cartopy.feature.NaturalEarthFeature is not very helpful, especially in regards to the name argument:

• name – The name of the dataset, e.g. ‘admin_0_boundary_lines_land’.

What are other available names? The class documentation refers to https://www.naturalearthdata.com/, but there are no names listed.

Some hint on how to build a proper name would be appreciated, or more examples in the gallery.

Cartopy version

0.22

[dopplershift]

It's tricky because Natural Earth doesn't really document those names either. You have to go to the download page and look at the URLs to pull out the name.

A pull request trying to simplify and succinctly document this would be welcome.