Multiscale hard dependencies

[VEZY]

Models that are hard dependency of another scale from which they were defined are not taken into account yet.

What we need to do is:

1. Put these models as hard-dependency children of the model at the other scale
2. Update the inputs/outputs of the parent model using the hard-dependency model

Step 1 is done already, but there is much difficulty with step 2.
The inputs and outputs variables are used for two distinct purposes:

• to compute the template status for each scale
• to compute the soft-dependency graph, which only uses inputs and outputs of models to know when each model should be run. The new difficulty is that now we should also check for models that are in other scales, checking if they have any variable that is computed by a hard-dependency model at the same scale that is currently computed.

If we update the variables of the parent model, they will be used to compute the soft dependencies at the scale of the parent model. This is not desired because the variable is not computed at this scale but at the other scale, so it is not present in the parent scale status.

We need to be more explicit on the way we manage variables and scales. We should probably use wrappers around variables in the dependency nodes already, to be sure where a variable is computed. Caution: the variables from the multiscale hard-dependency models are not multiscale variables! The models are just run from another scale, but the status is the one at the scale of the hard-dependency model.