Add tweet #ChaiScript link

Author: lefticus

_includes/header.html

@@ -74,6 +74,10 @@
       <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="https://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
       </li>
       <li>
+      <a href="https://twitter.com/intent/tweet?button_hashtag=ChaiScript&text=Embedded%20scripting%20for%20my%20next%20project%3A%20" class="twitter-hashtag-button" data-related="lefticus" data-url="http://chaiscript.com" data-dnt="true">Tweet #ChaiScript</a>
+      <script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0],p=/^http:/.test(d.location)?'http':'https';if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src=p+'://platform.twitter.com/widgets.js';fjs.parentNode.insertBefore(js,fjs);}}(document, 'script', 'twitter-wjs');</script>
+      </li>
+      <li>
       <!-- Place this tag where you want the +1 button to render. -->
       <div class="g-plusone" data-size="medium" data-annotation="inline" data-width="120" data-href="http://chaiscript.com"></div>