Documentation should specify the list of species for which spin-orbit coupling is available

Documentation should specify the list of species for which spin-orbit coupling is available. A clickable link to this list should be available from the documentation entry for the 'RelativisticCorrection' keyword.

I am running an H3S 3-D periodic boundary 'gs' LDA/default PSPs calculation using spinors, and just now saw a warning in the output that :

Info: Generating external potential

** Warning: ** Spin-orbit coupling for species 'S is not available.