First attempt to reproduce SpeedyWeather.jl humidity example

See https://github.com/SpeedyWeather/SpeedyWeather.jl/issues/737#issuecomment-2961973881 output.nc is a netcdf file containing fields for specific humidity, zonal wind, meridional wind, vorticity, etc. (ncdump -h output.nc for more details) parameters.txt specifies the model setup (see e.g., model.output in this file to see output variables) Model version corresponds to commit hash 53b38644b9a55e0bf0bf814566c52cd86e766907 of https://github.com/SpeedyWeather/SpeedyWeather.jl