Include XML variables for more specific non-global parameters

[TeaganKing]

Is your feature request related to a problem? Please describe.

We'd like to have a more configurable way of running CUPiD via the CESM workflow. We are currently working on adding options that allow users to adjust global parameters via xml changes. However, it would also be nice to include XML variables for more specific non-global parameters. Some examples of variables we will want to include are:

• cupid_seaice_climo_nyears = nyears
• cupid_seaice_base_climo_nyears = 40
• Other notebook-specific parameters

Describe the solution you'd like
This will require adding additional variables to config_tool.xml (in CUPiD), and also adding these to the helper script functions that create a CUPiD config file for a CESM case.
Additionally, in ccs_config, we will need to use XML Query to get the variables and pass them to the helper scripts.

Describe alternatives you've considered
We could also generate the config file during preview_namelist and then modify the config file by hand instead of running a bunch of XML changes.