Explicitly assign properties/fields in constructor of Supertype

[sshankar19]

constructor(objectTemplate = ObjectTemplate) {
    var template = this.__template__;
    if (!template) {
        throw new Error(constructorName(Object.getPrototypeOf(this).constructor) + ' missing @supertypeClass');
    }

....
//@todo: fill the properties of 'this' in? do I need this after deleting the callerContext approach

    return this;
}