ENH : Compatibility with MERRA-2 atmosphere reanalysis files

Is your feature request related to a problem? Please describe.

Right now, RocketPy has compatibility with ERA-5 reanalysis files from ESA only.

Describe the solution you'd like

It would be great if it was possible to use netcdf4 files from other agencies, like the ones from MERRA-2 from NASA

Additional context
The work to do this adaptation should be simple. Just need to use the function to read the ERA-5 file and do some adaptations for it to support the structure of the MERRA-2 Files

Bosilovich785.pdf