set_parameters only set value of parameters that exist already in the template model

[liunelson]

I notice that TemplateModel.set_parameters(...) only use those param_dict items that correspond to an existing parameter in the template model. It was a bit tedious to do TemplateModel.add_parameter(...) for each new parameter to which I want to set a value. Is it fair to ask for set_parameters to add any missing parameters and set their value as per param_dict?