Add support for more datasets in cluster_csa load routine

[jameswilburlewis]

When we first implemented the routines for loading data directly from the Cluster Science Archive, we were given a list of about 40 supported dataset IDs we could use in our server queries. But this isn't an exhaustive list: there are dataset IDs like C1_CP_CIS-CODIF_HS_H1_PSD
that weren't in the original list, but are available from SPDF (but using all lowercase names).

Unfortunately there isn't an easy way to convert the SPDF names back to Cluster dataset IDs (because some of the Cluster names are
mixed-case). But we can probably make a bit of headway making some of the SPDF data accessible via the TAP interface.

We'll probably need to abandon the approach of choosing from a fixed list of dataset IDs, but rather construct them on the fly from their components, like we do when constructing URLs for our HTTPS-based load routines.

There is a similar task for PySPEDAS: spedas/pyspedas#1319