Add test on toleranceMoveToCore and toleranceToInterruptSimulation Values

Raise an error if toleranceMoveToCore > toleranceToInterruptSimulation.
Closes #299
Add a check on toleranceMoveToCore existence if user forgets to provide one in the input file.

Set it as None by default then check that it's not None.
Before this change the error message was unhelpful: "model requires at least 1 argument (2 given)."
Closes #302