Check for wrong annotations

[casella]

Wrong annotations are silently ignored by the frontend. They should rather generate errors. Typical test case:

model M
  Real x(start = 1, fixed = true);
equation
  der(x) = -x;
annotation(Experiment(stopTime= 5));
end M;

simulates for 1 second instead of 5, because Experiment should be experiment and stopTime should be StopTime. Unfortunately, the compiler does not complain at all.