Write a check_config.py with basic config assertions

[FabianHofmann]

After tackling some issues with the spatial and temporal cutout bounds, it seemed sensible to add a dedicated script which reviews the config and basic ressources created during the work flow.

To start with: we should add an assertion for the following for

• all snapshots of the base.nc being in the cutout time selection
• the whole spatial area is covered be the cutout.bounds

[FabianHofmann]

This is the current bounding box for all grid cells (default config) and the offshore area, it seems not right that some of the offshore area remains uncovered. However I still have to figure out how the maximal distance of wind turbines plays out here.

[FabianHofmann]

After a small discussion with @euronion we agreed that it would be better to double check such configuration manners in a dedicated file.

Such would be named check_config.py and would contain basic assertions for consistency and validation. Atm for such a case as above where you to double check a ressource, it would probably contain function which you called here.

[fneum]

Could be called in Snakefile after

pypsa-eur/Snakefile

Lines 11 to 12 in 4d0a860

	configfile: "config.yaml"

configfile: "config.yaml"

assert check_config(config), "Configfile not correct."

With function definition either directly in Snakefile or imported from separate file (like scripts/_helpers.py).

[euronion]

In the PR we came across options in config.yaml which became deprecated.
It would be a nice addition to have the check_config(...) also warn about options in the config file which are deprecated (or soon will) and are thus without effect.

[euronion]

snakemake offers some basic config validation using a JSON file (details).
This could partially take care of validation (correct structure and types), deprecation and consistency validation between options cannot be outsoured to this functionality (I think).