Mention Fluid app on the About page

assets/javascripts/templates/pages/about_tmpl.coffee

@@ -71,6 +71,7 @@ app.templates.aboutPage = -> """
     <li><a href="https://sublime.wbond.net/packages/DevDocs">Sublime Text plugin</a>
     <li><a href="https://github.com/gruehle/dev-docs-viewer">Brackets extension</a>
   </ul>
+  <p>You can also use <a href="http://fluidapp.com">Fluid</a> to turn DevDocs into a real OS X app.
 """
 
 credits = [