code: function (modelName, modelObject) {
  
      // check for name, object and if model already exists
      if (!modelName) return ('Name is not defined');
      if (!modelObject) return ('Model in ' + modelName + ' is not defined');
      if (this.registeredModels[modelName])
        return ('Model ' + modelName + ' is already registered');
      var o = Object.create(modelObject);
      this.registeredModels[modelName] = deepLook(o, this.types);
      return false;
    }
docs: Register new model. Return 2valid object Parameters: modelName - name of the model, modelObject - model object