addIcon(type, options) {
    options = options || {};

    this._setPositions(options);

    return this.execute(commands.ADD_ICON, type, options);
  }
Add icon on canvas
@param {string} type - Icon type ('arrow', 'cancel', custom icon name)
@param {Object} options - Icon options
     @param {string} [options.fill] - Icon foreground color
     @param {number} [options.left] - Icon x position
     @param {number} [options.top] - Icon y position
@returns {Promise<ObjectProps, ErrorMsg>}
@example
imageEditor.addIcon('arrow'); // The position is center on canvas
@example
imageEditor.addIcon('arrow', {
    left: 100,
    top: 100
}).then(objectProps => {
    console.log(objectProps.id);
});