message: Extend the getType method description
diff: @@ -267,7 +267,28 @@ export class Base {
  }
  protected onBaseCreating() { }
  /**
  - * Returns the type of the object as a string as it represents in the json. It should be in lowcase.
  + * Returns the question type.
  + * Possible values:
  + * - [*"boolean"*](https://surveyjs.io/Documentation/Library?id=questionbooleanmodel)
  + * - [*"checkbox"*](https://surveyjs.io/Documentation/Library?id=questioncheckboxmodel)
  + * - [*"comment"*](https://surveyjs.io/Documentation/Library?id=questioncommentmodel)
  + * - [*"dropdown"*](https://surveyjs.io/Documentation/Library?id=questiondropdownmodel)
  + * - [*"expression"*](https://surveyjs.io/Documentation/Library?id=questionexpressionmodel)
  + * - [*"file"*](https://surveyjs.io/Documentation/Library?id=questionfilemodel)
  + * - [*"html"*](https://surveyjs.io/Documentation/Library?id=questionhtmlmodel)
  + * - [*"image"*](https://surveyjs.io/Documentation/Library?id=questionimagemodel)
  + * - [*"imagepicker"*](https://surveyjs.io/Documentation/Library?id=questionimagepickermodel)
  + * - [*"matrix"*](https://surveyjs.io/Documentation/Library?id=questionmatrixmodel)
  + * - [*"matrixdropdown"*](https://surveyjs.io/Documentation/Library?id=questionmatrixdropdownmodel)
  + * - [*"matrixdynamic"*](https://surveyjs.io/Documentation/Library?id=questionmatrixdynamicmodel)
  + * - [*"multipletext"*](https://surveyjs.io/Documentation/Library?id=questionmultipletextmodel)
  + * - [*"panel"*](https://surveyjs.io/Documentation/Library?id=panelmodel)
  + * - [*"paneldynamic"*](https://surveyjs.io/Documentation/Library?id=questionpaneldynamicmodel)
  + * - [*"radiogroup"*](https://surveyjs.io/Documentation/Library?id=questionradiogroupmodel)
  + * - [*"rating"*](https://surveyjs.io/Documentation/Library?id=questionratingmodel)
  + * - [*"ranking"*](https://surveyjs.io/Documentation/Library?id=questionrankingmodel)
  + * - [*"signaturepad"*](https://surveyjs.io/Documentation/Library?id=questionsignaturepadmodel)
  + * - [*"text"*](https://surveyjs.io/Documentation/Library?id=questiontextmodel)
  */
  public getType(): string {
  return "base";
  