gcm_setup python conversion

[sshakoor1]

The purpose of this PR is to fully rewrite gcm_setup in python, as a small start of a larger effort to refactor the GEOS codebase.

Some notes:

• Currently, only uncoupled AMIP experiments are zero diff from cshell
• gcm_setup has been uncharacteristically edited/expanded upon quite a bit this past year, so a lot of features have yet to be added (e.g. singularity sandbox, data atmosphere, etc.). In addition, some parts of the code may be outdated from the latest commit of the mainline script.
• jinja2 templating is being used, and in order for it to work jinja's delimiter syntax needed to implemented into all the template files. This means that all variables in gcm_setup that previously had the syntax @foo now look like {{ foo }}.
• Cloning experiments is still a work in progress and is not currently an option. In the future it will require passing in yaml files created from previous experiments.
• While this PR attempts to heavily refactor the code, it is not perfect, and probably needs to be refactored down the line itself.
• Can only be run on python 3.11 and higher. To run, simply navigate to ~\GEOSgcm\install\bin\gcmpy\scripts\ and run the command python gcm_setup.py

[tclune]

I'm wondering if there is a better name for this file. The filename should reflect what it is used for - not what technology it uses.

[sshakoor1]

Honestly this file should not be included in this PR, it is mainly a helper script for me. No one else should need to ever run this.

[tclune]

"utility" is a bit vague. Possibly a more specific name could be thought of?

[sshakoor1]

Yes I agree. Env and utility should probably be merged into a new script down the line. These scripts were kind of thrown together early on and desperately need to be updated.