Add a function implementation fo the library.

        :param name:        The name of the function as a string
        :param proc_cls:    The implementation of the function as a SimProcedure _class_, not instance
        :param kwargs:      Any additional parameters to the procedure class constructor may be passed as kwargs

def add(self, name, proc_cls, **kwargs):
        """
        Add a function implementation fo the library.

        :param name:        The name of the function as a string
        :param proc_cls:    The implementation of the function as a SimProcedure _class_, not instance
        :param kwargs:      Any additional parameters to the procedure class constructor may be passed as kwargs
        """
        self.procedures[name] = proc_cls(display_name=name, **kwargs)