Fix: JS Events will not register, if admin was loaded with direct url 

**Problem:** If a user edits a page in SilverStripe directly by calling the edit url (for example: http://mywebsite.com/admin/pages/edit/show/1), or hitting enter in the address bar instead off opening http://mywebsite.com/admin/ and then using the menu to get to the page, jquery-livequery is not used. Instead the tag-field events are registered using regular event handlers.

This leads to a problem if the user then select a different page using the menu. Because now we are missing livequery.

**Solution:** always use livequery no matter if the first request was ajax or not.