fix conflict with theme set in query and theme specified in head

index.html

@@ -334,7 +334,7 @@ function linkify( selector ) {
 				progress: true,
 				history: true,
 				
-				theme: Reveal.getQueryHash().theme || 'default', // available themes are in /css/theme
+				theme: Reveal.getQueryHash().theme, // available themes are in /css/theme
 				transition: Reveal.getQueryHash().transition || 'default', // default/cube/page/concave/linear(2d)
 
 				// Optional libraries used to extend on reveal.js