Add missing geoscience libraries

[maxrjones]

Geoscience libraries are rendered from the list here - https://github.com/pangeo-data/pangeo.io/blob/main/src/data/geoscience-libraries.js. I seeded the list with cf-xarray, but it would be great to add other Pangeo software libraries to that list.

[TomNicholas]

From the equivalent section of the xarray website: xgcm, xarray-spatial, metpy, verde, climpred?

Also xcdat? oh xvec too

EDIT: uxarray