site: load twitter snippet asynchronously

index.html

@@ -320,7 +320,7 @@
 		<script src="assets/jquery.min.js"></script>
 		<script src="site/js/bootstrap.min.js"></script>
 		<script src="site/js/main.js"></script>
-		<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
+		<script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.async=true;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
 		<script>(function(){var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true;po.src = 'https://apis.google.com/js/plusone.js';var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s);})();</script>
 		<script>var _gaq=[['_setAccount','UA-31081062-1'],['_trackPageview']];(function(d,t){var g=d.createElement(t),s=d.getElementsByTagName(t)[0];g.src='//www.google-analytics.com/ga.js';s.parentNode.insertBefore(g,s)}(document,'script'));</script>
 	</body>