model API improvement: validate_schematization

[DirkEilander]

I'd like to add a validate_schematization method to the model API which contains some checks if all the parameter maps, geoms (and forcing) are valid. Example of checks to include are checks valid parameter ranges, checks on locations (e.g. wflow res outlet in reservoir or sfincs src point in model domain), etc. The method returns a list of errors and a list of warning and writes these messages to the log file. Especially when maps are added manually / modified by users instead of using the setup_* methods this wil be useful.