Pass through any extra .trigger params in the event dispatcher

jQuery.trigger lets you specify the event and an optional array of extra parameters.  Those extra parameters were not being passed through by the event-dispatcher.  

With this patch, you can now do:
```javascript
App.view = Ember.View.extend({
  myCustomEvent: function(param1, param2, param3){
    ...
  }
});

Ember.$('#view').trigger('myCustomEvent', ["myArg1", "myArg2", "myArg3"]);
```