Feature/gsi validation netcdf

[ADCollard]

Description

Changes required to use netCDF files by default. Added missing routines for antenna correction coefficients.

Issue(s) addressed

Partially Resolves #192

Dependencies

None

Impact

Expected impact on downstream repositories: None

Checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have run the unit tests before creating the PR

[ADCollard]

Putting this Draft PR in for initial review. It is still a draft PR as:

1. I am still getting seg faults when running the code from the GSI
2. The changes to src/Coefficients/FitCoeff/FitCoeff_Define.f90 that were reversed are still in this version as we still need to address this.

Right now inclusion of CRTMv3 with GFSv17 is unlikely given the issues with seg faults.

[BenjaminTJohnson]

@ADCollard I was in Italy last week, so just now getting back to this today.