Make modifications needed to build a Python-wrapped version of SHiELD

[spencerkclark]

Description

This PR makes changes required for building a Python wrapped version of SHiELD. It does two main things:

• It builds all code except the coupler_main.F90 driver into static libraries, which downstream applications can link to (for now I did this only for the shield configuration option, but I could make a similar change for the solo configuration as well).
• It adds an option for build all components with position independent code, through adding a nopic / pic option to the COMPILE, BUILDlibfms, and BUILDnceplibs scripts, and adding an PIC option to the Makefile templates for the gnu, intel, and nvhpc compilers.

Fixes #27

How Has This Been Tested?

These changes have been tested in ai2cm/SHiELD-wrapper#1. The continuous integration setup there builds the fortran model and its dependencies using the COMPILE script, builds the Python wrapper, and runs several tests. An important test checks that the Python-wrapped model produces bit-for-bit identical results to the fortran executable for an identically configured run.

Checklist:

Please check all whether they apply or not

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] Any dependent changes have been merged and published in downstream modules

[spencerkclark]

Thanks for the review @laurenchilutti -- good catch. I added default values for the pic argument in all of the relevant scripts. Let me know if you'd like me to make any more changes.

[spencerkclark]

Thanks @laurenchilutti and @bensonr!