Merge pull request #667 from fourplusone/feature/cleaner_code

Removing unused code - All looks good, some minor tweeks are probably worthwhile  in the future.

src/static/js/timeslider.js

@@ -24,7 +24,6 @@
 // assigns to the global `$` and augments it with plugins.
 require('./jquery');
 JSON = require('./json2');
-require('./undo-xpopup');
 
 var createCookie = require('./pad_utils').createCookie;
 var readCookie = require('./pad_utils').readCookie;