Link best practices, and removed font for faster loading time

web/dart/navbar.dart

@@ -54,6 +54,7 @@ Element makeShareLink(Element icon, String url) {
     ..append(Element.a()
       ..attributes['href'] = url
       ..attributes['target'] = '_blank'
+      ..attributes['rel'] = 'noreferrer'
       ..append(icon));
 }
 

web/dart/reorganize_html.dart

@@ -2,7 +2,8 @@ import 'dart:html';
 
 import './navbar.dart' show makeNavbar;
 
-const image_header = 'https://cdn.phundrak.com/img/mahakala-monochrome.png';
+const image_header =
+    'https://phundrak.fra1.cdn.digitaloceanspaces.com/img/mahakala-monochrome.png';
 
 Future<Element> makeHeader() async {
   var header = Element.tag('header');