Fix timezone JS parsing that worked only on Chrome

- Sometimes you don't have GMT but UTC
- Sometimes you don't have spaces character after timezone code

ko Firefox 20 "Wed May 01 2013 13:24:00 GMT+0200" (space missing)
ko IE10 "Wed May 1 13:24:00 UTC+0200 2013" (UTC)
ok Chrome26 "Wed May 01 2013 13:24:00 GMT+0200 (Paris, Madrid (heure d’été))" (still works)

Because of that Categories & products could not be edited and saved in IE/FF browsers

Bug:
http://forum.broadleafcommerce.org/viewtopic.php?f=13&t=1830&start=0&sid=5d8edb0cbaaeb35958be809898e4b5d7