Wikia tracker changes bugid 45483

More info can be find here: https://wikia.fogbugz.com/default.asp?45483

Basically, there were two issues:
1. Javascript error in the console in Firefox because we don't have global event object in Firefox
2. Ctrl + click on links which are being tracked didn't work as it should (it opened new page in the same tab instead of new tab and sending tracking data).

We still can think of better way of implementing our click tracking. But this one seems working correctly and I smoke tested it and didn't find any regression. If you're OK with this changes we can merge them and resolve ticket #45483.