Improved ax_lib_netcdf.m4

[underwoo]

A large refactor of the ax_lib_netcdf.m4 macros. This update better supports systems that don't have working n[cf]-config applications

More work still needs to be done, as there are large sections that are essentially copy/replace and can be better organized.

Fixes #19

[underwoo]

The check are failing due to csh not being available in the Docker image. Although, if csh were available the checks would still fail as the scripts are written for use on the NOAA RDHPCS PPAN system. #22 should fix that problem.

[ngs333]

FYI, I also checked that it builds on AMD + Ubuntu Linux.

[laurenchilutti]

I've looked over the code, and just to do a simple test, I installed this on Orion and it worked. As long as you know why the checks are failing and feel it is ready to merge, it looks good to me.

[underwoo]

I've looked over the code, and just to do a simple test, I installed this on Orion and it worked. As long as you know why the checks are failing and feel it is ready to merge, it looks good to me.

The tests are failing due to not having csh or the sample data for one or more of the tests. There will be issues and PRs to resolve those later.

[mlee03]

I only tested compilation on Gaea and Skylake where there were no difficulties setting the NetCDF configurations with nc-config, so it wasn't an extensive test. The comments in the .m4 file are very helpful :D