feat: Pass kwargs to model load via optimisation wrappers (#1096)

Allow passing keyword arguments to models via the optimisation wrapper.

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Co-authored-by: Stefano Simoncelli <Stefano.Simoncelli@dwrcymru.com>

pywr/optimisation/__init__.py

@@ -60,6 +60,7 @@ class BaseOptimisationWrapper(object):
     def __init__(self, pywr_model_json, *args, **kwargs):
         uid = kwargs.pop("uid", None)
         self.pywr_model_klass = kwargs.pop("model_klass", Model)
+        self.pywr_model_kwargs = kwargs.pop("model_kwargs", {})
         super(BaseOptimisationWrapper, self).__init__(*args, **kwargs)
         self.pywr_model_json = pywr_model_json
 
@@ -107,7 +108,7 @@ def model_constraints(self):
         return self._cached.constraints
 
     def make_model(self):
-        m = self.pywr_model_klass.load(self.pywr_model_json)
+        m = self.pywr_model_klass.load(self.pywr_model_json, **self.pywr_model_kwargs)
         # Apply any user defined changes to the model
         self.customise_model(m)
         return m