code: function setProperty(property, newValue) {
              var originalValue;
  
              if (newValue != originalValue) {
                  originalValue = this[property];
                  this[property] = newValue;
  
                  this.dispatch('change:' + property, {
                      originalValue : originalValue,
                      newValue      : newValue
                  });
              }
  
              return this;
          }
docs: Sets the value of a property.
  @method setProperty <public>
  @argument property <required> [String] the property to write.
  @argument newValue <required> [String] the value for the property.
  @return [Object] instance of the model.