Added an image for the playground project

src/app/constants/AssetsConstants.ts

@@ -15,6 +15,10 @@ export class AssetsConstants {
   static readonly DIPLOMA = '/assets/projects/diploma/Dahm2010-Diplomarbeit.pdf';
 
   //project images
+  static readonly PLAYGROUND_IMAGES = [
+    '/assets/projects/playground/1.png'
+  ];
+
   static readonly EL_MUCHO_IMAGES = [
     '/assets/projects/el-mucho/1.jpg',
     '/assets/projects/el-mucho/2.jpg',
@@ -43,4 +47,4 @@ export class AssetsConstants {
     '/assets/projects/tribble-the-homeserver/3.png',
     '/assets/projects/tribble-the-homeserver/4.png'
   ];
-}
+}