Calibrate parameter inside Blocks of Simulink Model

[lvanfretti]

We need to modify RaPId so that the parameters inside of Simulink can also be changed, and not only the parameters of the Model in the FMU.

The use case is control design using Simulink controller, while the plant is in the FMU.

@tinrabuzin maybe we can ask Ravi to spend some time on this, please explain him more in detail.