Fix Haxe3 & Add Tab

I experienced some compilation problems with @freakinruben's compatibility code, so I fixed these and use the opportunity to add my code for Bootstrap's Tab.

Tested with this code, works like a charm:
```haxe
var tab: JQuery = new JQuery(".nav-tabs a");
tab.tab();
tab.click(function(e){
    new JQuery(e.target).tabShow();
});
```