add favicon

layouts/_default/baseof.html

@@ -9,7 +9,10 @@
     <meta name="robots" content="noindex">
     {{ end }}
     <link href='/styles.css' rel='stylesheet' type="text/css" />
-    <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+    <link rel="icon" href="/icon16.png" sizes="16x16" />
+    <link rel="icon" href="/icon32.png" sizes="32x32" />
+    <link rel="icon" href="/icon64.png" sizes="64x64" />
+    <link rel="icon" href="/icon128.png" sizes="128x128" />
     <link rel="canonical" href="{{ .Permalink }}">
     {{ if .IsTranslated }}
     <link rel="alternate" hreflang="{{ .Lang }}" href="{{ .Permalink }}" />