added other size icons

site/assets/manifest.json

@@ -1,16 +1,53 @@
 {
-  "name": "Hacker News PWA",
-  "short_name": "HN PWA",
-  "description": "Hacker News readers as Progressive Web Apps",
-  "theme_color": "#F4751E",
-  "background_color": "#FFFFFF",
-  "start_url": "/",
-  "display": "standalone",
-  "icons": [
-      {
-          "src": "/assets/images/favicon.png",
-          "type": "image/png",
-          "sizes": "512x512"
+    "name": "Hacker News PWA",
+    "short_name": "HN PWA",
+    "description": "Hacker News readers as Progressive Web Apps",
+    "theme_color": "#f4751e",
+    "background_color": "#ffffff",
+    "display": "standalone",
+    "Scope": "/",
+    "start_url": "/",
+    "icons": [
+      {
+        "src": "/assets/images/icons/icon-72x72.png",
+        "sizes": "72x72",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-96x96.png",
+        "sizes": "96x96",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-128x128.png",
+        "sizes": "128x128",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-144x144.png",
+        "sizes": "144x144",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-152x152.png",
+        "sizes": "152x152",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-192x192.png",
+        "sizes": "192x192",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-384x384.png",
+        "sizes": "384x384",
+        "type": "image/png"
+      },
+      {
+        "src": "/assets/images/icons/icon-512x512.png",
+        "sizes": "512x512",
+        "type": "image/png"
       }
-  ]
-}
+    ],
+    "splash_pages": null
+  }