Optimise all assets (PNGs, fonts, and GIFs)

Please see https://git.ari.lt/muyrety/uselis.eu/pulls/1 and https://git.ari.lt/muyrety/uselis.eu/issues/2 for further recommendations.

Signed-off-by: Arija A. <ari@ari.lt>

pages/guides.xhtml

@@ -15,7 +15,7 @@
 
 		<title>=Purple Guides=</title>
 		<link rel="stylesheet" href="/assets/css/style.css" />
-		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="icon" href="/favicon.png" type="image/png" />
 	</head>
     <body>
         <!-- Sick ascii art/logo -->