Fixed issue with mobile nav choosing the last option by default. Fixes #950.

.themes/classic/source/javascripts/octopress.js

@@ -11,6 +11,7 @@ function getNav() {
   mobileNav.children('select').bind('change', function(event) {
     if (event.target.value) { window.location.href = event.target.value; }
   });
+  mobileNav.children('select').val('');
 }
 
 function addSidebarToggler() {