Parameter system does not check allowable range

[Prof Garth Wells]

The range or allowable strings for a dolfin::Parameter can be set, but the parameter system does no checking that user set parameters are allowable. Checking allowable parameters early picks up user errors.

[Andrew Taber]

Is the expected behavior to throw an error if the user attempts to use the assignment operator when the range has been set?

Additionally, should there be an error thrown if a parameter range is set after the value is set but the range does not include the value?