Validation for MPC

[EserSteffen]

It seems MPC validation is a bit outdated. For example, if inputs are incomplete an error might not be raised anymore, raising casadi errors instead. The user should not be confronted with casadi as much as possible

[FWuellhorst]

An example:
If you pass a CasadiInput to the list of states, you get

  File "D:\05_Programme\anaconda\envs\BESRules\lib\site-packages\agentlib\core\model.py", line 186, in __getattr__
    raise AttributeError(
AttributeError: 'MPC' object has no attribute 'differentials' 

Even though the property exists. Calling the property would raise "CasadiInput has no attribute ODE", not sure why this is not the message one gets.