message: added new `shadow` prop to Image
diff: @@ -1300,6 +1300,13 @@ declare namespace PptxGenJS {
  * @default false
  */
  rounding?: boolean
  + /**
  + * Shadow Props
  + * - MS-PPT > Format Picture > Shadow
  + * @example
  + * { type: 'outer', color: '000000', opacity: 0.5, blur: 20, offset: 20, angle: 270 }
  + */
  + shadow?: ShadowProps
  /**
  * Image sizing options
  */
  