Empty constructor for models with fields with default constructor

[AlexPl292]

Empty constructor for RdWrapper is expected using this model

val RdContent = classdef {
    property("myProperty", string)
    field("myField", string).default("Default")
}

val RdWrapper = classdef {
    field("content", RdContent)
}

but RdContent should be explicitly passed as argument: RdWrapper(RdContent()).

RdWrapper should have empty constructor because myProperty is property and myField has default value.