PASE - Implement storing weather data as cache file

Summary Weather data should be stored locally once the user has downloaded, for two reasons :

• it will make following computations with the same inputs faster (i.e. running the simulation does not require accessing the PV-GIS API, which is the biggest overhead in the current simulations)
• it will make it possible to run PASE when offline (useful while in transit, etc.)

The aim is to store these cache files in a format easily readable (with pandas.DataFrame.to_csv() ? so that we can directly use pd.read_csv() during following simulations), in folder INPUTS/WEATHER_FILES/CACHE.

TO DO

• Check the feasibility of storing weather files (@simone.lucisun)