Don't show parameter edits in FMU created with ealuate all parameters

[massimo ceraolo]

When we create an FMU while "Evaluate all parameters" is active, parameter values are hard-coded in the FMU. When we later use the FMU, no trace of this characteristic is there.

Steps to reproduce:

• open FMUissue.mo.
• create a ME FMU from Gain
• load the FMU, open Test and connect the output of realExpression to the FMU input
• simulate: the output is (correctly) constantly equal to 2
• change K from 2 to 4 in the variables Browser => the output does not change to 4. This is because in reality K=2 was hardcoded in the FMU
• go in the modeling perspective, double click on the FMU and change gain1_k from 2 to 4, and simulate => the output is still 2 (again, this is because K=2 is hard-coded in the FMU).

This behaviour, although correct, and clear once one has understood what happens, can be very confusing in the beginning.
I think that when we create FMUs with the option "Evaluate all parameters" active, it should be impossible to change parameters either from the FMU dialog (before simulating) or from the Variables Browser (before re-simulating).