Longitude reordering from [0, 360] to [-180, 180]

This includes a function in the default nes which reorders the longitudes of a netcdf from [0, 360] to [-180, 180]. It also includes an entry point where users can access the longitude reordering feature directly from the terminal:

nes_reorder_longitudes input_path.nc output_path.nc

So far, these functions are only available in serial.

A testing script was added, and a path in the bash to run the tests in mn5 was edited to avoid permission errors.