Create model cleanup utilities

[JoerivanEngelen]

With the introduction of model validation, users now have some good feedback of what is wrong to their model, for example a model that I recently imported:

E           imod.schemata.ValidationError:
E           Simulation validation status:
E               * imported_model model:
E                       * riv-2riv package:
E                               * stage:
E                                       * not all values comply with criterion: >= bottom_elevation
E                       * riv-3riv package:
E                               * stage:
E                                       * not all values comply with criterion: >= bottom_elevation
E                       * riv-5riv package:
E                               * stage:
E                                       * not all values comply with criterion: >= bottom_elevation
E                               * conductance:
E                                       * nodata is not aligned with stage
E                               * bottom_elevation:
E                                       * nodata is not aligned with stage
E                               not all values comply with criterion: >= bottom
E                       * riv-5drn package:
E                               * conductance:
E                                       * nodata is not aligned with elevation

However there is not so much guidance on how to fix things. To help them, I think we could create some cleanup utilities, which need to be very well documented on how they clean up data. Users then still need to make the calls to the functions themselves, so that they are aware what they are doing.

Requirements

• Create a namespace, like imod.cleanup for these utilities, becomes part of public API
• Extend ValidationError messages with hints to the appropriate functions to call
• Well documented cleanup utilities
• Add utilities for:
  • Masking all cells in inactive model domain. mask_all_models basically does this.
  • BC: Aligning nodata for a boundary condition
  • RIV: Setting stage above bottom_elevation
  • RIV/DRN: Setting stage/elevation equal to model bottom
  • More?
• Add example showcasing these utilities
• Add cleanup utility wells #1187

[JoerivanEngelen]

The first steps are introduced in #1172, wells and other cleanup utilities (NPF?) are still to be added. As for the validation messages and the examples.