Merge pull request mermaid-js#108 from athiramanu/bug/3_link_recent_fontawesome_stylesheet

Updated fontawesome stylesheet link

Author: sidharthv96

docs/index.html

@@ -9,7 +9,7 @@
 	<link rel='icon' type='image/png' href='favicon.png'>
 	<link rel='stylesheet' href='styles.css'>
 	<link rel='stylesheet' href='bundle.css'>
-	<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
+	<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.2/css/all.min.css">
 <!-- Google Analytics -->
 <script>
 	(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){